I've been saying it for a while, as has Rugrat. We've said it to each other, in fact.
Personally, I rate Greer as being our best defender but that doesn't mean to say he's what you want if you're challenging for the Premier League. He has the technical class and he has the positional sense...
This thread is EXACTLY the same as all the others on him.
Ultimately, what's so difficult to understand? He's been here so long people have now decided he's the weaklink, and he technically is because we've improved all over the pitch and the centre backs are the position which is unchanged...