Cheers for that Sylvanilo, all makes sense. I've only been fishing the seacourt the last three seasons or so, and I definitely agree that the fishing is patchy. That said, I've never known it be any better or worse (over the course of those three years, not really enough time to get a sense of the decline I guess?)
What I will say is - it's thrown up a few very pleasing surprises in that time - a small barbel, a 5lb+ chub, a trout that took a liking to cheesepaste (had it twice in the same swim on different sessions...). There's also a couple of bits that seem to fish pretty good with trotting gear, never massive fish but dace, perch and roach have all put a bend in the rod.
I guess what I love about it best is that it reminds me of some of the streams I fished on when I was a kid... where if you wanted to be successful, you needed to approach the river with an open mind. If you turned up saying to yourself - "today I will quiver tip with bread in this swim".... then chances are you might not catch at all. But if you turn up with a couple or three different baits and different ideas about how you might present them, depending on the situation you're faced with - then you might do better.