As Todd says, the prop cages take care of the fishermen, but I don't see motorboats having problems with them out there. But I don't have any experience with a trawler in Maine water(as he said, no AP, you'll have to be hands on the wheel at all times.)

I think Bruce has it right, the problem isn't as bad as it's made out to be - for most boats(as cchesly says-some boats are stickier than others).

I hit them often under power by mistake, and pay almost no attention to them under sail(they clunk along the bottom then hit the dinghy-which is a good sound to hear). For about 20 seasons, I've hooked maybe 7 or 8 and only had to cut 2 that I recall. But we've never wrapped the shaft tightly.

If I can't remove it, I just pull the warp up with a boat hook, cut it and re-tie. We've never had to dive, have no wetsuit-hook knife.