I agree with Mward I have some with and without and have not noticed any real trend either way. Lately I have been seeing more boards made of clear plastic for sale and wondered how that would help not seeing the board at all. We do tend to pay more money for fluorocarbon so they cannot see our leaders so maybe not seeing the board could help with easily spooked fish. Truth be told I have no doubt one could be caught with a beer can and bailing twine on the right days.
Ids say the majority of my largest stripers have come within 5-8' of the planer board. I'm not sure the fish care. Theres plenty of videos of fish trying to eat waterwolf and similar cameras, so I think we give them too much credit.