User blog comment:Ofi123/Powerleveling kanmusus/@comment-61.148.244.103-20141027164237/@comment-25361436-20141027174839

That would only be roughly a 2% increase in artillery spotting chance, I believe. Sure, it does help, and you'll likely only be using 2 or 3 slots of attack planes on your CVLs, since more tends to be unnecessary, but it's still a really small increase.