nothing wrong with posting it to keep the party kids out. and hey, it IS his land, he doesn't HAVE to let anyone through, but he seems like he doesn't mind fisherman, if so, we should be grateful to be allowed through.
for those that fish it often and use his land, get together, meet with him, tell him how appreciative you are, get him a case of beer, a gift certificate for somplace, or whatever. trust me, stuff like that goes a long ways, much further than thinking your entitled to cross his land just because you always have. Not saying that is the case here, but I've seen people act that way, some people just don't understand the word "private"!
maybe get in contact with PFBC about access in that area, maybe they will work with the landowners to come to some comprimise.