People use floating lights to catch crappie! I really don't think its a big deal. Try it if you like it and catch fish its all good. If you go out and blank, you can blame it all on the light. I use a light at night all the time, we have flipped and pitched close to the bank and caught several really big bass. It is fishing not rocket science. I say if it helps you see or aids in casting, go for it. Plus its cool when you get a bite and you see the line jump about a foot. Wakes you up on those slower nights.