No, I don't mean stopping the human in their tracks, I mean wallwalking on them. Considering in real life (ok maybe not real life), the person would probably flail around to dislodge the dretch, a human with a dretch walking on them could jump or boost to shake them of. Another way to lose a clingy dretch might be to scrape them against a wall.
I've also thought that bsuits should be able to step on dretches and crush them. Perhaps these two features would balance?