I have spider rigged as slow as 0.1 mph to as fast as 1.0 mph, depending on what the fish want. Whenever I make a turn and start catching fish on the outside rods, I know that I either need to speed up or shallow up.

While I haven't fished with minnows for about 10 years, they do work when the bite is tough on artificial lures. I typically use two jigs tied via loop knot about 14-16" apart on average--bottom one may or may not be a roadrunner/spin fin style of jig head depending on what they are biting. My typical weight is 1/16 oz each, although I have gone down to 1/32 oz each. Sometimes I use a little extra weight to keep them down; sometimes I don't.