To get back to what Bobco said, brace height can be as much a culprit in fishtailing as bad releases and arrow spine. If you're sure you've got the right arrow, then fiddle with that brace height. The way you describe your arrow flight, I'd twist up that string to raise the brace a full 1/2" immediately and go from there.

I disagree with Adams about his comment on gloves. Poor quality gloves, and tabs too for that matter, can take a crease and cause the string to hang up. Good leather will not crease. I've become partial to what they call 'super leather' on Neet and Black Widow tabs. Cordovan leather tabs are also great. Damascus gloves and the SuperGlove from Alaska Bowhunting Supply are the best gloves out there, IMO.

The real advantage of a tab over a glove, at least when considering nothing but shooting, is that a glove lets all your fingers act independently. so a finger or two might drag on the string as you release. A tab pretty much forces your fingers to act as one unit. When one finger releases, they all release.

An old timer's tip: get yourself one of those little travel size bottles of baby powder to carry with you when you shoot. Powder your glove or tab once in awhile to slick it up. Target shooters used to have little leather powder pouches to hang on their belts with a hole cut out in the front, covered by cloth. When you wanted to powder up, you just patted the cloth. You might still be able to find them, but I haven't checked around.

And don't weenie out and get a release.[8D] Give your fingers some time to toughen up and they'll quit hurting. I'd advise getting a thick tab until your fingers get in shape, like the Neet PFT - the one with the felt finger spacer and superleather face. My all time favorite tab.

I don't recommend tabs with calf hair faces. They're great at first, but when the hair starts wearing off they get inconsistent.