Polite and clever indeed...well put. I must add though, it is acceptable to give an artist a few things to do that you think might improve the composition. This isn't a command, it's merely a suggestion, and I myself always appreciate a suggestion from other artists, and almost always take them at least into serious consideration, if not implementation. My only complaint is that when i put up a WIP and ask for critiques, I get very few replies. I really would like more advice on my works, that's why i post them to the forum and ASK for critiques before i make them gallery pieces.