Ah, that explains why it wasn't working for me, then! I figured it was going to be more of an issue of pressing jump at the right time than just pressing it a bunch.

Thank you so much!

I've been trying to figure out how to do the shield jump as performed in Dea1h and 666Deadhunter's runs, but it's not really clear to me exactly what's happening, much less how to replicate it. Any explanations or advice?