Could it be presentation differance, angle, line size etc.? I have only seen it maybe make a fiffereance in gin clear water and even then who really knows? Fisherman spend way to much time chasing colors, baits etc. Whem almost without excpetion you need to find them and get a bait in front of them. However to each his own! Also arn't you all refering to fishing a buzz frog style bait for a reaction bite? They for sure cannot pick up on the added purple or whatever color flake if that is the case.
Paul-
If I'm not mistaken, aren't you the owner of Wave Worm now? If so, don't you guys have a variety of colors as well? There's a reason every bait company on the planet has multiple colors to choose from. Some staple colors, but a lot of different colors also. This goes for hard baits as well. Everything you mention above (presentation difference, angle, line size etc) also play a role. But I honestly feel color choice is main ticket item you have to have going for you to get bit.
On the buzz bug, its not a frog at all. It's a smaller compact craw with a little longer pinchers that move a little more water than some conventional craws. But its compact enough to flip in tight mats of grass.