If you just ever so slightly step into the boss room whilst shooting, the gates don't close and the boss can't damage you but you can damage them.

Does this allow you to instantly go to the right?

And iirc, this happens because some projectiles carry over to the next screen, like those enemy towers that shoot bullets, their projectiles can cross over to the next screen a little bit

It does not allow you to move past where the gate is but it does make the boss fight easier and could be used to make the run faster, I will try get a video tonight to show you guys