Don't know if this is old news, but this happened in a run:

I just crashed the helicopter into the wall as usual but it resulted in me clipping into the wall and warping slowly upwards, just like it happens in level 3 and level 25 when clipping through a ceiling from a slope.

No idea if this is actually useful anywhere though.

Would love to know how to get the Helicopter clip in the last level of Love 3 :(. Tried several hundret times, got it once and was not able to replicate it. This way i can't use it in my runs (would be my ticket to get sub 12 in any percent for now)