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Comment Re:It could (Score 1) 133

They're passenger (and freight) trains. The rails were built for travel, not for scenic display.
OTOH, the sure aren't high speed rail. Most of the lines were build over 50 years ago.

OTOH, the BART example was for a "high speed train", though I believe the speed is limited underground. But the rise is from perhaps two or three stories below ground to about 1 story above ground. That said, I believe that the rise is about 2-3 miles long, so it's not steep.

Comment Re: It could (Score 1) 133

Sometimes using the highway ROW works, other times it doesn't. This partially depends on the design of the highways, and partially depends one whether they have the same destination. A train station under a section of elevated roadway can work well...but if you don't have that convenient elevated roadway things can get more difficult.

I can't even estimate costs, but they can get pretty high. (And sometimes it's easy.)

Comment Re:It could (Score 1) 133

Since there are trains that go over the rocky mountains, I think that argument fails. (But it might succeed if you argue practicality rather than possibility.)

FWIW, The SFBay Area BART system has high speed trains that move from elevated to underground. It's not a steep grade, of course, but it's done. (IIRC "high speed" for the BART system is around 70 mph, and is only obtained on the long straight sections. Of course, my knowledge is multiple decades old.)

Comment Re:No. (Score 2) 133

There are also real problems with sparsely available origin and destination points. And the cost of building the lines through developed areas.

If you build a good system, it will be more efficient for the areas that it serves. But rail transit has fixed routes. This makes it inflexible. And you really need to multi-track the rails, because breakdowns will occasionally happen.

FWIW, I feel that streetcars are much more plausible/effective/significant per unit cost than are high speed rails. High speed rail is useful AFTER you solve the local distribution problems.

Comment Re:LLMs don't hallucinate (Score 1) 59

Agree about the meaning of "hallucinate" in this context, but...

You can't be sure your brain is deterministic. It may well have features that operate at the quantum level, with the implied genuine uncertainty. Transistors are normally scaled to avoid that problem. This isn't exactly "free will" in any normal sense, but it *is* non-deterministic behavior, at least as far as we can tell. (Yeah, superdeterminism is a valid interpretation of quantum theory, and so is the multi-world interpretation and a few others that take the entire universe as context. So in some sense it's still deterministic, but it's a really weird sense. And as far as the Copenhagen interpretation [i.e. "shut up and calculate"] goes even in that sense it's non-deterministic.)

Comment Re:The talented ones can (Score 1) 256

Thus 5x3 becomes 5x5x5 or 3x3x3x3x3 instead of "STFU and memorize your times tables."

I'm fine with the repeated addition. My objection is the OR in your statement. Apparently not. The question was 5x3 and the kid wrote 5+5+5=15 and got marked wrong with no explanation because the teacher wanted 3+3+3+3+3=15. So I guess that you would have had a 50% chance of being marked wrong on a 2nd grade arithmatic worksheet as well, as absurd as that is. Correct answer notwithstanding.

BTW, that's not at all new. We covered multiplication that way in the 3rd grade back in 1975. Memorizing the table was just to make it quicker. I quickly "discovered" the commutative property while looking at the multiplication table and cut my memorization load in half. The part that confused the father was why is 5x3 = 5+5+5=15 "wrong".

As for 37+55, we decomposed that in the '70s as well, but I soon decided the easier decomposition was 37+55= 87+5 = 90+2=92. So I would say that meme was just someone wanting to complain. Of course the "old way" ends up in 30+50+10+2 anyway.

Shut up and memorize was not in practice during the education of the parents of today's students.

Comment Analogy to BMW Subscription Heated Seats. (Score 1) 104

...re trying to make so forgive me if I am out to lunch, but this matters naught to the consumer. This is just back-office dealings that either adds $5 to the cost of a laptop or doesn't. It's there vendors choice what licenses they pay or don't pay. Then they get to set the price on their laptop after it all shapes out.

If the hardware is still present, but is disabled, you're still carrying around the hardware. Most importantly, you're probably still powering its logic even if it's inaccessible to you.

BMW, like most German cars, is overcomplicated and overpriced garbage sold only to self-proclaimed car enthusiasts who wouldn't know how to change a tire let alone a timing chain. BMW got themselves into a bit of controversy by including heated seats which only functioned by subscription.

Now, say I had bought a BMW but didn't want the heated seats. I don't pay for the subscription. There's no additional cost to me, the purchaser of the car, because the profit from the people who do opt for the subscription are the ones paying the cost of the extra hardware in my car, correct?

Wrong. I am now carrying around an extra-beefy alternator to power the heated seats. I am now carrying around all the extra wiring to power the heated seats. All of this impacts my performance and my fuel efficiency. And all of this extra complexity adds a failure liability when something damages part of the heated seat hardware. All for a feature I specifically did not ask for by refusing the subscription.

With a disabled chunk of logic embedded in a processor, is it a negligible cost and a negligible risk? Maybe, but as the purchaser, it's crap that I didn't ask for, and you are imposing on me. If I have to carry it around and power it up, I expect to be able to use it.

If the manufacturer doesn't want to supply a feature then they should not supply the hardware. Leave the spots on the circuit board unpopulated. In the case of a chip, leave it off the die.

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