Single target is one of our stronger points in that it's better than our burst AoE.
Moonkin's true strength is sustained AoE, really shining in spread AoE (think a council fight where each boss has to be 10yrds apart)
Concerning the patchwerk sim, as others have said there's only so much that you can conclude from it. In a real single target boss encounter there are mechanics that will change the action list, and in general that means every class gets lower numbers than listed here. Movement impacts some classes more than others (melee have virtually no penalty if they can stay in range) and the amount & type of mechanics vary from boss to boss. There's no way to correct for mechanics and pull out a good estimate - this is why people always tell you to take sim results with a mountain of salt.
Based on what I've seen, in the 5 major archtypes of boss fights we are:
Pure single target - Just below average
Single target w/ burst cleave - Well below average
1 boss w/ long-life adds - Slightly above average
Council - Above average
Multi-target (think Spoils of Pandaria) - slightly below average
All in all, nothing to write home about.
I also think despite some individual's best efforts the APL is quite far from optimal. I need more experience before I can really guess how though.