Blue and White are awesome together and use it a lot. The thing that makes me jump on Blue so much is what I read about colors and visibility. To make this short and sweet Blue and Violet are the colors that can be seen. Red and such are the one that disappear first, I suppose just look grey or something once far enough away in water, even crystal clear water. In that crystal clear water the Blue can be see at 40'. However UV and Florescent colors change this as far and distance they can be seen.
i figure the first thing that helps in getting bit is visibility or just being seen.

Now ow take bass, a bass can see 5' to 7' in muddy water and 15' to 17' in stained water so I figure crappie can also see much farther than we can in the water.