Perhaps the worst form of bad etiquette is when guides with clients in tow disrespect other anglers. Last year, I was on the Dream Stream in Colorado, minding my own business, enjoying some dry fly action, and all of the sudden out of nowhere, a guide and 4 clients completely top-holed me, about 50 feet upstream, above where my casts were. The guide didn't even acknowledge my existence, but interestingly, one of the clients did. I was forced out, reeled up, and off the next spot I went. Maybe that is a tactic I'm not familiar with by some guides.