Not that I'm stuck on shad Bill, but I have been reading that fishing guides in Miss. on some large lakes attributed thier record size crappies in recent years to high density populations of TFS & GSHD, along with larger minimum lengths 12"+ .
I don't know what the nutritional breakdown of what a 3" shad is compared a 3" shiner or other minnow species, but I think it would have much more.
Electro shocking is a shot to the wallet, which I would end up investing in my own DIY boat setup along with a few other few pond owners nearby that could burden some of the scratch.
