I have always thought about this. Many years ago when I was a kid I used to fish various Rapalas 80% of the time. The plain black and silver ones were a million times better than the ones with a fish pattern on them. I am mainly talking about the shad raps. I believe that with detail you give the bass a chance to find something wrong. A negative cue. I have always thought that a plain spinnerbait, buzzbait, crankbait, or jigs should have a simple pattern. With the exception to jigs, bass dont have a lot of time to decide if they are going to eat those baits or not. I dont like jigs with eyes or scales or a detailed head. I like them simple. Now keep in mind NONE of these baits are realistic to begin with. They have bills or hanging trebles or splitrings etc. To me cranks get bit becuase of the illusion they create. Not on the detail. Now as a swimbait maker I feel this is completly diferent becuase the most common method is to fish the baits as slowly as possible and LET the fish get a good look at them. If you realy want to get a bite on a swimbait cut off all the hooks and use 4lb Fluorocarbon in a clear lake. You wont catch a fish and you will get your bait bit off but you will see that the little details help. Think about a plastic worm being worked along the bottom. There realy isnt much a bass can find that looks wrong except the line.
One more thing I always here that lures are made to catch fisherman instaed of fish. I disagree. If a company invests the time and money they want a bait that will continue to sell. One that does not produce will quickly die off. However I do believe that lure companies do make many diferent sizes and colors of a good product to capitalize on sales. I myself have done this. The ones that our out to catch the fisherman and not the fish are the knock off companies. They will copy good designs to make a quick buck. This is the main reason that originals are almost always better than copies. Not always but most of the time.