I am not sure if it works the same way in this game, and I didn't notice anywhere where it would save time, but in Mario 4 you can kind of "store" P-speed by releasing the run button. You lose P-speed if you bump into a wall, but not if you stop running, as long as you are still moving forward.
It works the same way in Mario 3. It was done a number of times to reach platforms where jumping at full speed would make Mario run into a wall and lose P-speed.
PJ wrote:
This is probably not the place to ask, but I'm curious about what emulator issues are preventing Mario 4 from being TASed. When I was practicing, I noticed that the worse emulators (Gens, etc) had a final boss fight whereas Bizhawk just reset when you completed the final platforming level. I assumed it was an emulator bug, but playing on an "authentic" physical copy, it behaves the same way as Bizhawk. The game resets when you complete the final stage and you don't fight the final boss. Probably a tricky ruling to make...
I was thinking it's not emulator issues but actually the consequence of playing the game on a more accurate emulator. Even if Mario 4 was allowed to be TASed on Gens, I don't think I would do it as it lacks something like TAStudio and the traditional use of multiple save states and frame advance isn't something I'm used to.
Disabling Address Errors allows the game to continue to the boss, This is an option in Genesis Plus GX.
Additionally, not emulating the Z80 bus control (allowing both the 68k and Z80 to access the bus at the same time) allows the BGM to continue playing after a PCM sample has played (e.g. bricks breaking, Mario falling, pipe sounds, etc.)
The question remains if you should resort to intentionally making the emulator inaccurate for this.