Given how wide Slashdot's readers are, I suspect the reason why people are picky is because there's the expectation that a lot of people reading will be not native speakers--and having been a regular of IRC chatrooms where we were chatting in English purely because it was the sole language everybody knew, it was hard to miss sometimes that while people fluent in a language certainly can 'fix' missing words...this required fluency.
Frankly, this is the first time I have had this problem. I've been posting on BBSs, IRC, Usenet, Compuserv and usually, the only thing I used to get dinged for is spelling. As spell checking has gotten better, I have been able to "see" the way the word written correctly looks like, and more often than not, notice that it is "wrong", but usually can't tell you why it is wrong.
How well do modern STT options work? I was a selective mute because it took years to get it to where my speech could be understood--it was simply less frustrating to not even try to talk--so I'm very wary of attempting to get a computer to understand my speech.
I haven't used computer based STT, but I am having good success with Android's version on both phones and tablets. I am going to have to see soon about getting some sort of STT running on Linux to see how good it is...I hope that I won't be forced to shift to Windows to get decent software....although in theory, the stuff Google is doing should be portable to Linux since, at it's base, Android is running on top of Linux. Android apps are really just like Java apps, as they run their own bytecode in a sandbox on top of something else, like the Linux kernel.
As for keyboards, I've found that HP, ASUS, and Lenovo's laptop keyboards work well for me, enough so that I've actually worn out a couple laptop keyboards. I also keep a cheap USB old-style keyboard in my Bin O' Cables. (I am not going out to buy a new keyboard in the middle of the night, thank you.)
I used to use a Happy Hacking keyboard, but I switched to using a KVM between two machines, and thus needed to switch to a USB keyboard. I am currently using logitech wireless keyboard & mouse combo as I was forced for a while to work in a very limited space, but I now have enough space to maybe move back to the HH keyboard, or buy a new mechanical one, and switch back to using a trackball.
Incidentally: Choose a craft or musical instrument you enjoy that requires deft hands, the skills do transfer! This is a way to try to force your brain to expand the region associated with your hands, as well as increase manual dexterity, and the skills will transfer. (It won't help your handwriting, though; my handwriting is and remains dismal in English. I have reason to suspect that'd require having to relearn it entirely but have seen no sign that anybody's done the research here...yet.)
I actually play guitar, and have played for about 20+ years. I'm no Jimmy Page, Jeff Martin or Alex Lifeson but with practice I can play along with some of the songs they wrote. :-) I also play synthesizer, which is a bit different from just playing keyboards...playing a synth involves knowing more than just what keys are what notes, but understanding things like waveforms, envelopes, LFOs and all sorts of esoteric "analog programming" to produce unique and intersting sounds.
This might also help you when your eyesight gets worse, since being able to work by touch is amazingly useful when you're working in the dark or in conditions where you can't see (well). Personally, I think it's a useful skill for anybody to have; if nothing else, being able to change a lightbulb in the dark has its obvious applications.
As it is, when I turn off the light when I go to bed, I don't turn it on again if I need to hit the restroom, and thus navigate in the dark. It's not much, but it gives me a feeling for moving around without sight. Luckily, Macular Degeneration tends to just remove the sight in the middle of the eye, so you get sort of a "reverse tunnel vision" type of blindness, that is, you can, see around the outside of your field of vision, but not what you are looking at directly. So getting around is one of the few things that is not as bad as for those with total vision loss.
BTW, it has taken me over an hour to write and then edit this....hopefully it's not too bad. :-)