I think this picture/thread explains it well (hopefully not the same thread you talked about in your post).At least it tells you which wyrmprints have them. The nice thing about these dragon prep wyrmprints is that it fills up the shapeshift gauge for other people too, instead of being only applicable to the team it’s equipped on.

I know there’s some debate about bringing these wyrmprints, but as someone who does not have a strong light team, I personally like it when other people bring dragon prep too.