Bo, I see your point and there was a time when I did the same. But two factors have changed my mind in recent years ...
First, fishermen in general seem to want everything handed to them these days, including how/when/where to catch them. I know there have always been some like that, but now it seems to be more the rule than the exception.
Second, there is a fair number of guys these days who run their own businesses off the front of their boat using cell phones. You give these guys a spot(s) and they'll flat wear them out. And if you give them a pattern, some of them are good enough to put 2+2 together and end up on your spot(s).
Yeah, I'm getting old and crabby to a degree, but the truth is I enjoy sharing most of what I've learned over the years. I just don't like handing it out to the lazy bums who are just looking for an effort-free leg up on the competition.