OK ; maybe I'm a bit too close to the data to read the article without bringing knowledge from other areas to bear. The sequence as best we can determine so far is :
(1) T0 : Deccan Traps start erupting (along with the Reunion volcanics, probably, from the palaeogeography)
(2) +170,000 years : Chicxulub impact.
(3) + short period, maybe up to ~60,000 years : Dinosaurs and many other groups start going extinct.

Although, given the imprecision of the timing for large, long-lived animals compared to short-lived ones, it is possible that (2) and (3) are more like :
(2) as above;
(2a) +months to 1 year : direct impact damage, fire and starvation do for large dinosaurs ; small dinosaurs and other meso-fauna survive ; dung beetles can't find enough fresh poo piles ;
(2b) +10 years : ocean pH has dropped by 3 units (1000x more acid) ; major extinctions of marine microflora ; seeds from previous flora are germinating, but with an absence of large herbivores, there are drastic ecological changes (compare what happened to the US/Canadian steppes when the bison was almost extinguished).
(2c) +20 years : ocean pH rebounds by 1 unit, but many large marine life forms starving to death (or reproductive inability - same thing).
[...] continuing series of sequels for millennia.

Disentangling such a sequence will be a real challenge, given that in deep marine sediments (our most stable environment, where you're likely to get the most consistent records without storms taking out the critical metre of sediment), it's perfectly possible to have bioturbation (worm burrows) stir things up through a metre of sediment thickness - a good million years worth. Of course, we could look at a K-Pg analogue of the Euxine Sea (a.k.a. "Black Sea" ; the archetype euxinic basin where the bottom waters are nearly sterilised by hydrogen sulphide because of restricted water circulation) if we (1) wanted to look at only planktonic organisms and (2) we could find such a basin (any suggestions? I don't know of one off-hand, though I've not studied the question. When I'm working next year in the Black Sea, I'll maybe do a literature search).

On the other hand, we're not extinct yet, and have certainly been around for millennia. The only difference is that for the last century or so, effective contraception has been available.

Aldous Huxley may have been predictive.

There's a reason laws against witness tampering and the like exist, you know. It's because people really will do this, and a lot of people believe--rightly or wrongly--that if all the witnesses are gone, the case will fall apart.

Which is of course, part of the reason that the police rely as much as they can on forensic and surveillance data rather than witness data. While emotionally effective for juries, witnesses do have a distressingly poor memory, easily fooled by both themselves and the cross-examining lawyers. And if a witness gives evidence that emotionally affects the jury, but the judge then instructs the jury to disregard (for example, because forensics show that it can't be accurate), if the jury then convicts there an open channel for an appeal and running through the whole dog-n-bone show again. which is a waste of money, brains and time for everyone concerned.

It caused enormous damage

On a human scale, yes.

Human scale isn't the appropriate unit of measure. This is a volcanic event ; as volcanoes go, Mt St Helens wasn't much more than a fart and a squirt. It just happened to be a fart and a squirt that impinged on human-inhabited areas.

I'm trying to remember the numbers on Mt St Helens - not committed to memory as so unimportant an event - but it's about the scale of the current Bardarbunga event, plus or minus a factor of a couple? It wasn't a Pinatubo.

That's not the only problem. Most of the world didn't have significant volcanism before, during, or after the impact. The areas that did have volcanism - say one eruption every 1,000 years, per volcano - carried on with that at with a barely detectable difference. Much the same for earthquakes - only those areas prone to earthquakes before the event had earthquakes, and within a few thousand years (probably) after the impact even the area around the impact would have settled down within a millennium or two. (It would have been pretty wild for the first few hundred years though!)

The are proposing that this strike didn't have any secondary effects - such as volcanoes, earthquakes and the like?

No, they're not. They're saying that some of the main effects which have previously been attributed to this impact actually occurred before the impact. Therefore the main effects are not things that were caused by the impact. Minor things (huge earthquakes ; mega tsunami ; hundred-metre thick rains of red-hot glass spherules) were limited to the Caribbean basin and surrounding areas (up to Canada, probably down to Paraguay, possibly well into Africa), and these minor effects are not a matter of dispute at all.

IMO ... such a LARGE impact would have ramifications for MANY years to come.

You've missed out a factor of 100,000 or so. The evidence from the ground is that it took several millions of years for the biological diversity of the planet to return to pre-impact levels (and then with a changed cast of dinosaurs, increased mammals, and a severely changed marine microflora and somewhat changed invertebrate fauna).

It does say that.

Well, it is thought we've found all the dinosaur-killer-size asteroids,

That's sort-of true for asteroids. Astronomers think that they've found around 90% of the expected population of Earth-crossing multi-kilometre Main Belt asteroids. But if the models are wrong, or we're looking at a non-Main Belt asteroid ... then that 90% figure doesn't hold. (And 90% found still leaves 10% un-found.)

However, an impactor coming in on a cometary (Kuiper Belt or Oort Cloud aphelion) orbit is another matter. Considerably higher impact velocities and therefore energy ; considerably shorter warning times - down to a few weeks, easily if you remember Hyakutake ; no good idea of a mass distribution. It's an open book.

While we're living in one ecosystem, we're vulnerable at the species or kingdom level. It'd take a lot to eradicate the single-celled organisms, but plants and animals are much more vulnerable.

biostatigraphy and high resolution geochronology [show] that the impact event took place between 100-150 ky BEFORE the KT mass-die off that defines the K-T boundary

The last time I read one of Keller's papers while the ink was still damp, she was pushing for around 60~75 kyr between Chicxulub and K-Pg, with around 200kyr between the start of the Deccan and Chicxulub. Which is a real triumph of differential geochronology on a global scale - error bars of around 0.1% of value for two events which are reasonably close to antipodal.

I've never found the antipodal argument convincing.

It has never been convincing energetically.

The improvements in dating over the last decade or so have killed it dead. It has shuffled off this mortal coil and gone to join the Choir Immortal etc etc. It is an ex-hypothesis.

While the hypothesis laid out before us may never have been called "beautiful", it was at least a respectable. And here it is - laid low not by one ugly fact, but a swarm of fact-flechettes tearing it to shreds. Alas, poor Yorick-the-antipodal-eruption hypothesis. I knew him, Horatio. Poor sod never stood a chance.

Unfortunately, the process that formed the Deccan was the process that led to the separation of the Indian plate from the African plate.

As part of that process, extension of the area before separation led to the tilting of substantial fault blocks as well as the transport of mudrocks to considerable depths and temperatures, where they cooked to produce hydrocarbons (oil and gas) which then migrated upwards into traps formed in the tilted fault blocks.

Which might just possibly give a hint as to why the area has been the subject of intense scrutiny in the last few years. When I first worked there, there wasn't an offset well log for 500km in one direction and 2500km in the other direction ; now there are about 6 major drilling programmes working the play, churning out a couple of new wells a month.

Yeah exactly, which came first? The pallet is virtually useless without the fork.

I would suspect the fork - as an adjunct to the portable crane. It is still very standard practice to move items of machinery around in the workspace by picking them up between the tines of a fork lift. Some fork tines have a hole pierced in the tip of each tine for looping soft rope or a chain through. And I've seen load spreaders and specialised barrel lifts which work in essentially the same way as a set of fork lifts still in use on construction sites. I suspect that the crane modifications came first - as many factory floors have a crane of some or several sorts, and they can use the same adaptors - and the pallet then co-evolved with that.

When I first started working on industrial sites in the latest 1970s there were still several different sizes of pallet in use, and from certain advertising (e.g. for vans : "our bed is wide enough for a EuroNorm pallet") I suspect that there are still several nearly interchangeable sizes still in use. (The EuroNorm is TTBOMK 1m in dimension with a few cm handling leeway on either side. I wouldn't be surprised to find that a USian pallet is one Edwards-nose-fingertip (three Roman feet or a "yard") on edge. That's a nearly 30% difference in volume.

No.

We still have to worry about astroblemes. A repeat of (for an example) the Chicxulub impact would certainly devastate the Western hemisphere. Think of tsunami washing [I forget the name - range of hills along the north edge of Texas. Ozarks?] as kilos of red hot debris falls on every 10 sq.m of the hemisphere, with the subsequent conflagration.

It might not be a species-ending event for Homo sapiens, but that would be due to our wide geographic range and the presence of locally abundant stores of both food and information. It might well be a civilisation ending event, or at least put us back to around the Renaissance. Fairly big deal.

If it had happened a mere 14 kyr ago, it could have extinguished pretty much the whole of the human race. Or at least, if it took out the appropriate area, wiped out agriculture for a few millennia. (14kyr BP is the approximate date of the Barringer crater.)

And yet you participate in the corporate - consumerist love-fest by using telecommunications, electronics, and electricity. But since you don't want the responsibility of change, you probably don't vote.

The Wilkes' Land structure is credible. However about 5 (10?) years ago another structure was proposed as the "Dimetrodon-killer" (Dimetrodon was a scary toothy land animal of the time. A "mammal-like reptile", IIRC.) The "Bedout" structure off NW Australia is about the right age A plagioclase separate from the Lagrange-1 exploration well has an Ar/Ar age of 250.1 ± 4.5 million years.

However, the hypothesis that a major astrobleme is necessary to trigger a Large Igneous Province at the impact's antipode does not have strong support. (Possibly it has no significant support - we have a very incomplete impact record.)

The hypothesis (implicit, but never as far as I know proposed by a serious scientist) that a Large Igneous Province (LIP) is incapable of causing enough global environmental stress to cause a mass extinction is not proven. LIPs come in many sizes, and since they tend to bury their early phases under their later phases, it is very hard to measure their actual durations and eruption rates.

The hypothesis that a large astrobleme is sufficient to cause a global mass extinction has not been proven. In fact, the classical case - the K-Pg or Chicxulub impact - itself shows an inconsistent story. Some dinosaurs died out (large ones) but small dinosaurs survived and are now the most species rich group of tetrapods (birds). Some free-floating plankton families died out (damn, where's a biostratigrapher when you need one?) and other, closely related families didn't. Some plant families died out, and others didn't.

Contrary to what "popular science" programmes will tell you, the pattern of extinctions at the K-Pg extinction seems almost random. Which suggests that the Chixulub impactor was not, in itself, sufficient to take out all of a group of life forms.

Possibly, to get a mass extinction, you need to combine a LIP (which is happening around 1/10th to 1/5th of the time) with another "point event" (impact [K-Pg], methane-clathrate destabilisation [Pg-Eo], ocean sulphate chemistry fuck-up [Palaeozoic-Mesozoic], or another impact [Manicouagan + 2 others in a chain, Triassic-Jurassic]). It isn't a simple story. But it's more likely to not be incorrect than the simple story.