ok, I've got some fun updates today. For now, it looks like the alternate Zero^2 setup for GT1 is not useful, as it requires exit at first guard. If you do the guard skip, and save progress to level 2, the setup sends you to the room with the other guard, rather than to the room directly above. In other words, you'd have to do the guard exit, the full setup, and then play level 1 all the way through again. So it'll be 10+ seconds slower.
As for the alternate Gate Thief Sprite Set, it does seem to have promise. The setup is very cooperative, and I've been able to use it several times in a row, without a single mess up, or freeze. It also works just fine after completing Level 1 and saving progress to Level 2. Furthermore, as soon as Alternate Gate Thief is acquired, and Level 2 begins, there does appear to be much less lag than standard GT1. So Alternate GT gets off to a great start with 38 seconds saved on setup, and slightly faster level 2 from better lag.
Levels 2, 3, 5, 10, 15, 16, 17, and 20 appear to be identical to GT1 in terms of abilities, and no limitations to cause slow-downs.
That leaves levels 4, 6, 7, 8, 9, 11, 12, 13, 14, 18, 19. We already have a good idea of the potential for levels 18, and 19 from your TAS test, which loses about 78 frames altogether. So that just leaves 4, 6, 7, 8, 9, 11, 12, 13, and 14 to stay within 36.5 seconds of GT1 to be better, averaging 4 seconds per level. Early scouting reports reveal that it should be well below this mark on each level, with only a few delays here and there. After playing the other levels, it feels like each one only has about 2 seconds worth of delays, due to slower movements in approaching gates, etc. So I think we're gonna find that this would be about 18-20 seconds faster than the best GT1 route.
I noticed in your full TAS for this alternate GT sprite, that you intentionally collided with the wall to fall short of the gate before the boss on Level 18, so you could get a full jump into the boss room. This will be a 26 frame improvement, plus the 1 animation save in the hallway below the end button, that's 30 frames, or a full half second. So I can tentatively put the GT1 full projection around 81,344 - 190 = 81,154 = 22:30.34278943492. (160 for alt setup, 30 for better Level 18). I know there's another 8 frames to be saved elsewhere, which would bring it down to 22:30.209675327 with 13 more frames needing to be saved in order to reach a sub-22:30 for GT1. So if the new Alt Sprite is 18 seconds better, looks like the Warpless Route may have a potential for 22:12 or better.
I think it may be appropriate to refer to this alternate GT sprite as GT2 or Gate Thief #2, as it certainly seems to have priority over any other alternate gate thief sprites in the context of the Warpless Category, (like wobbling sword GT, or Fat GT).
