Jim Riedel, owner of Waterstreet Custom T-Shirts and Art Gallery in Rockport, told me that the crab fly is his go to fly when sight casting to reds. He says to cast the fly near the red, wait, don't move the fly for a few minutes. If the red doesn't pick up the fly, give it a couple of quick jerks. Jim is the type of fellow that when you meet him, you know you have made a friend and he really gets excited about fly fishing. He swears by the crab flies and got me started tying them.
The crab flies are sinkers. Jim says that reds inhale them. If you do go to Rockport sometime do check out his shop. He has a new process for printing T shirts like you see at FTU or Academy. The prints are done very smoothly and don't have the latex buildup that you see on some T shirts. Just tell Jim that the tall Basque guy from Houston sent you. Jim's grandmother was also Basque.
that will make it easy to connect the dots visiting the shop...are you keeping a running wish list for me? also I remember one time when we went snapper fishing anf those "ruby slippers" had their guts full of small crab very close to the size you have pictured..hhuummm another light bulb moment?