I prefer the "neutral" term "angler." I'm pretty impressed that someone took the time to figure out what "Iasgair" (which I can not pronounce) means I wear many hats, and half of them are Gaelic and virtually unpronounceable by English speakers. Sun has taken me fishing, and he knows me from another forum, as well.
I agree with everything you've said there, and that is what I was attempting to convey.
It is hard to qualify what constitutes "experienced" however. And, the context it was used in by the gentleman who caught the trout can't be determined by what has been posted. It could be that he's spent a couple years on stocked ponds, in which case he could say he was "experienced." He could have hunted a number of species of fish in a wide variety of settings, which would also constitute "experienced." Experience says nothing about skill level: especially if one has been doing it "wrong" for years.
In addition to that (with regards to your previous response to me) I don't think "guilt" has much to do with fishing "experience" or "smarts." I would say that guilt is a complex emotional reaction brought on by doing something that is contrary to one's personal ethics or morality. One's personal ethics and morality are developed and governed by a number of things: many of which I believe are more cultural than anything else.
I was raised to eat what I kill. I was faced with a situation this last winter that left me feeling very guilty and conflicted. I gut hooked a pike under legal size, and ripped out an important chunk of its insides when I removed the hook. I did what was legal (and "smart"). I put it back in the water to die, but I felt guilty about it. If I'd taken it home to eat it I wouldn't have felt guilty, but I would have been guilty of poaching. Emotions (especially "guilt" and "shame") are far too dangerous to rely on for guidance.
Maybe you could make a fish handling workshop available to the Sundance residents? Some literature that could be handed out at the gate might be a good idea too. While there would certainly be some people who felt they didn't need it, hopefully enough people would implement the techniques that the culture would slowly change.