If you hav'nt read my post about this !!! search for it, and the link to Mike's main article on crabs on this website.......
Crabs move / swim sideways - so - put the hook in the "back" "side" of the crab - so it pulls it along . . . and - - YES - - it does make a difference . . . .
Use a grip wire , or simillar , to make a hole , save the point on your hook for catchin the fish !