The instruction booklet refers to the elimination of two or more rows/columns as "continuous capsule elimination". So I suppose eliminating one row/column would be "capsule elimination" or just "elimination". However, I think most people simply call it a combo when there are 2 or more, and "match" seems fine to me for describing a singular instance.

In multiplayer, doing a combo of 2 matches drops 2 pill segments on the opponents screen, 3 matches drops 3, and 4 drops 4. You will never get a bigger drop than 4 even with many more matches. Therefore it is a good idea to be comfortable with making 4 match combos if you are playing multiplayer.

Here's a video where I do some combos with well over 3 matches:

All right, well, it is true that "it doesn't matter if you spin them a bunch or wiggle them left and right.". I guess it's the "end up in the right place" part that I think might confuse. There is no "right place". All that matters when deciding the pill colors is at what instant you press start in the menu. At that moment all your pills for all future levels are decided, until you either game over or go back to the menu some other way. So if you want to change some detail of say level 5 in the Any% WR, you can still use the exact same level 6-20 as inari80000. Or if you want to go Glitchless with what aiqiyou suggests, you could, if you wanted to, play the exact same level 0-20 every time without memorizing a 30 minute run.

"The shape of next capsule depends on where you place the previous capsule. Your push-button and capsule's rotation direction will not influence the RNG." Two sentences with opposite meaning? Just to clarify: The capsules' colors are determined at the same time as the virus distribution. RNG-wise, it doesn't matter where you place the capsules. This is easily verified, since the capsules come in a repeating sequence of length 128. So just count to 128 capsules, and you will see the pattern repeating.

Yeah, amazing run inari80000! It's really cool that you managed to go from that TAS to a RTA on a console.

I've been putting quite some effort into figuring out more about the freezing and glitching. I made a post about my findings here: https://www.twingalaxies.com/danielw/wall/3961/dr-mario-or-how-i-learned-to-stop-worrying-and-love-nnes Perhaps this can help to get even faster runs.

Don't hesitate to ask if you have any questions. @inari80000, let me know if you want me to translate any of it to Japanese.