Well, I read about the legality about dredging hermits and do not believe it is illegal to dredge for them. To help clarify things, I went to the DEC website and could not get a hint at the legality or illegality of harvesting hermits. (Remember that more hermit crabs are kept as pets than are consumed for the human palate.) I will check with them (DEC) by phone on Friday. I did speak with them 5 years ago about harvesting and was told that there was nothing on the books regarding them. Perhaps it has changed. I will look into it.
As far as the effectiveness of hermits, I believe that they are unbeatable as a bait for tog. In the days before limits and closed seasons, etc. (10 - 12 years ago) I used to anchor off the beach in the middle of July (in the off season when they are not supposed to bite) and catch bulldogs as the fluke boats would casually drift by me. Green crabs were almost useless. The point is that you will not always do as well with the greens. They are not just as good. Yes, some days the fish will be on suicide missions and it won't matter. But on the average day or the finicky ones, I'll choose the hermits.
The point made about the dredging and the effect on the bottom is questiomnable since the place to capture most hermits is along sandbar type habitats. These locations are the waters outside of the beach house colonies on L.I. Sound. The scallop dredge works best when it skims along the bottom. This is not to be confused with a clam dredge which digs 6 - 12 inches into the bottom. In fact, if the dredge does dig into the bottom, it stops the boat operator from working the dredges effectively. He or she must accelerate and thus continue the skimming process.