4. Anyone who writes “period” as a way of re-enforcing a previous point.
6. Anyone using multiple exclamation marks or caps lock.
Irony, intended or not? The children need to know! (Editors comment: Ignore that second sentence, it's him being him again)
On a relevant note, for anyone in the UK watching The Voice UK (I have no idea what the judges are like from The Voices around the world). Will.I.Am is one of our judges and I've noticed that he really doesn't like giving constructive complements. Early on in the contest he was full of constructive criticism for everyone but as times gone on and he's getting more competitive he seems willing to point out flaws in the other judges teams, but when they do well he doesn't like to say what they did well because he doesn't want to help them (I presume). He doesn't point out the flaws of his own team live on air, but I imagine he's more honest with them when they're off air.
So, my point. I respect him less as a judge because he lets his own agenda rule his criticism rather than being honest, but I'm not sure that actually makes him a bad critic. It comes under the field of “Why is this person reviewing my work?” In this case it's because he's obliged to but the less he says the better for him.