Told the story about fishing down at Watts Bar Res. in East Tenn, many years back, where I was getting little tiny bumps .... kinda felt like I was dragging my jig down a concrete sidewalk, not in open water. Several times I did see Shad running along behind the jig, and knowing that there are "Tenn Tarpon" in those waters I figured they were just bumping into or possibly nipping at the jig. Well sir, after about 10 or so retrieves with all this nonsense going on I was just about to move to another location, but I got kinda P.O.'d about the whole situation & set the hook ... basically out of frustration. I think I was more surprised than the Crappie I hooked, when I did finally jerk the rod.
Seems that, all along, it was 12-15" Crappie doing all that "nipping" ... and to be sure I laid the hammer down on "any" unnormal feeling after that !!