Ip?
 

Any rule code...

Hands separated.
Steps onto PP.
Hands come together.
Hands separate.
Pitching hand swings back, then forward and up.
Non-pivot foot swings forward, pivot foot drags along the ground.
Foot-swing and pivot foot-drag come to a complete stop when the windmill is still considerably high (maybe 2 o'clock), such that one might see this as a new push-off point.

It's a slow windmill action that causes this effect.

Illegal?

NCAA, absolutely illegal. The drag foot may not bear weight prior to release of the pitch.

ASA/NFHS, probably illegal. It's hard to picture this action not generating a push from this new spot, but both sets require a new and second force from this new spot to be considered a replant. But, it is possible that it is simply a legal drag that ended early, prior to release without a second push.

Ala this video?

https://www.youtube.com/watch?v=NnRdBRVopFg

Thanks guys, the video was close, but it's the "may not bear weight" that is the crux of my question, and that's what was happening.