Hello, I hope I'm not asking any dumb speedrunning noob questions that shouldn't belong in this forum. I've just seriously begun about a month ago to practice maintaining p-speed in any% no wrong warp, since my previous best was 13:25 without maintaining p-speed and getting pulled down by the first hand in world 8, and I want to try to get my time down to at least sub-13. My current strat is to get the mushroom in the bouncy block in 1-3, but I can't figure out how to consistently maintain p-speed after getting the mushroom, every time I do manage to maintain speed it's always by accident, and I can't seem to find any tutorials on when exactly to push A (I'm assuming it requires a precise time to tap A afterward, like maintaining speed after exiting pipes and doors, which I can't figure out either); if anyone can offer some pointers or point me to a tutorial, I'd be very grateful. Also, from watching mitchflowerpower's runs, I can't figure out how it's possible to not crouch on the white block at the end of 1-3 and still get behind the scenery, and I can't seem to find any info on how it's done either. Would anyone be kind enough to offer some pointers on this as well?

Someone else may be able to give you a better answer, but basically for 1-3 you can do the strat where you dont land on the goomba like in this video (which has input display aswell) .That strat seemed easier to me and the input display helps alot for learning it. As for the white block you just have to be holding down on the d-pad to go behind the scenery you don't have to actually crouch. Hope that helps

Should also point out you can ignore the random up dpad presses in the input display in that video. Also you may not want to do the strat where you jump over the koopa at the start

Thanks chinkenfish4, a couple of questions if I may:

1. it looks like when you jump up and eat the mushroom you let go of the A button, and then at some point afterward press A again to jump while maintaining p-speed, all while keeping B down throughout. I can't seem to find the exact instant for that second A press, is there some cue in Mario's growing animation you look for? I've succeeded in doing that maybe twice out of a hundred times, I just can't figure it out.
2. I've also tried to jump over the koopa at the beginning, only succeeded in doing it once without landing on the block above it, now I've basically given up on that and just kick the shell to get rid of the hammer bro. I know it should only be a light tap on A, from the looks of it you also let go of B for a split second? I might add that I'm playing on OpenEmu (Nestopia core) on a Mac using a PS4 controller (wired, not over bluetooth), could there be timing issues in emulation that differ from original equipment for these precision button presses?

EDIT: I'm dumb, just notice you're also using emulation. How do you get the input display in there? I've always wondered what software to use. And is that an 8bitdo controller?

I didnt record that video. Was just something i found while i was learning the game so im not really sure

But as for when to press A, i just do it when mario lands back on the wooden block, it wont work it you do it while mario is growing. You can also hold right the whole time if you want, don't have to release it like in the video