I've checked myself and it certainly too high to make a ideal connection with the tile boundary.
EDIT: I did some testing on the first level and I managed to get the weird running effect seen in Level 2 of Nitsuja's WIP, although sadly Mario lost a huge amount of momentum activating the trick, so it ended up being slower, it does make me think though could activating the effect at the start of level 1 save time.
http://dehacked.2y.net/microstorage.php/info/5540/Super%20Mario%20Bros.%203%20%28U%29%20%28PRG1%29%20%5B%21%5D%20Genisto.fcm
If a one frame improvement can't be found, I have a different route through the level which is 3 frames slower, but would at least mean you don't have to sacrifice time at the end and would prevent viewers from thinking that they've witnessed an obvious improvement/mistake.
EDIT_2: Sorry my mistake, being there quicker meant you were able to sacrifice time in order to get the mushroom card.