I've never heard of shad taking bait, unless you count the shad scales I used to use on a bare hook years ago. Thought it might be a mating reaction but have never confirmed why they'd "strike" at them. Shad are supposed to be filter feeders, eating plankton. I read in latest STS mag letters to editor that they eat smolts, but I find it hard to believe!
The chartreuse darts do seem best in the Columbia, with gold hooks.