I think Wooly might have gottoen hold of the wrong end of the rod. I don't think any of us were saying targeting well-known fish was inherently bad, just inherently boring!
The problem with it is two-fold. In the first place it eliminates the mystery, since you know for a certain fact the life history of the one fish you are trying to catch. Thus it does away with the donkeywork (which for me is the fun) of walking round every blob of blue on the Landranger map, sussing whether it's poachable/legally fishable, climbing trees to see fish, talking to other anglers about what they've caught in it.
The second reason relates to this; joining the circuses means you aren't actually thinking about a vital element of your fishing; the theory. All the detective work which results in 'new' fish being found is done by creative, intelligent anglers.
So everyone else is really riding on the shoulders of these giants. Nothing wrong with letting other people spot potential then using superior skills to fully realise that potential, but nothing beats following up some 'noddy's' catch in AT/AM with a visit to the water and showing what's REALLY there to be caught.
Round 'ere, there are hundreds of gravel pits and miles of river and drain. I've just come back from a bike ride round about 5 miles of bank. I spotted five anglers. It's Sunday. The amount of fishing effort currently going into 'wild' waters is so minimal, nobody can claim we have any idea of what's around to be caught.