I've heard the color on the belly should be lighter than the top.
(I agree, in nature, most anything that swims is patterned that way)
I've heard the all black, or all white thing too.
75% of the time, I don't think it matters...
then you get a month, where if it isn't say "pink".. they don't bite..
(saw that last fall)..

Maybe it's all confidence, I dunno.. but it sure is spooky if you have 5 guys throwing the same plug, and the three with pink catch, and the other two don't, until they throw something pink....