Quoted for truth. If the line clear delay was removed completely, the "average" players Mewtwo is so worried about would likely not even notice.
It may be possible, but it's quite difficult. Utilizing T-spins, you can send an average of 50% more garbage with the same amount of pieces. I just made that number up, but it seems reasonable, since you can't expect to send garbage with every single I and T piece.
Yes they would. Raw newbies don't fully understand line clears, and they're especially confused by hurdles, which occur often as a newbie tries to progress to setting up 3- and 4-line clears. They give the player some quality time to inspect those rows that aren't animating and find the holes that he or she left. And imagine how incomprehensible cascade gravity might be without delays.
Here's the difference: Snaking makes a poor to average MKDS player very good. There's not a ton of complexity of MKDS- it's all about who can get to the finish line first and snaking is a way to do something very fundamental in the game (move forward) much better. Using t-spins doesn't improve one's skill or speed. A poor to average player who learns t-spins won't become a very good player without improving other areas of his game (speed, efficiency, etc).
You don't have to remove the animations to remove the delay. The fastest players could keep track even if the animations were cancelling or overlapping; everyone else wouldn't notice.
I think we're all missing the real issue here. You have to consider the circumstances behind the techniques. 1. T-Spins can be done by both players. Snaking, however, is limited to the cart you are using (3 out of how many carts?). 2. T-Spins has an "equivalent" move in effectiveness: the Tetris. Snaking does not give other carts that option.