I don't know, that feels like it's really on the margins? Assuming pointless fishing would only be allowed when water temps are safe for fish , then it's hard to imagine getting a fish to rise for a hookless fly would have any measurable impact on the fish or fishery? I think a fly tied on a short plastic tube would reduce the possibility of an 'incidental' hookup to almost zero too. That said, I'm just another guy sitting in an easy chair offering an opinion....
That said, they still have to expend energy they wouldn't otherwise have to expend (obviously not as much as being hooked and played, but still).
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