In my opinion, I don't think color or contrast is nearly as important as action. The thing I believe makes Whiggley so versatile in so many fishing conditions is the way in which you can make them ... weight, softness, and rigging method. Depending on the weight you can use one Whiggley as a teasing slow twitch style bait that just hangs in one place and drives fish crazy or by adding tungsten you can get it to dive and twitch or burn it as fast as you can reel it and it will still stay 1' under the surface, or no weight and skip the thing on the surface like a fleeing baitfish. The softness is also key. The softer ... equals more deliberate hard kick out upon stopping it after burning the bait.
The shape and design are the trick. One you have a good mold, you can dial each Whiggley into its own charactreristics for specific situations. Does a contrasting tail help, I believe so but not as much as other factors Whiggley has built into its design. I like very natural colors for very clear water. For more murky, high pressured and virgin water ... I just think showing the fish something they've never seen before makes a significant difference ... much more than color.
Mike