My time usually is minimal also, excluding keywording but that is cause I hate it. Not the greatest in photoshop and so usually it is just fast global edits or some minimal contrast, dodge, burn in Camera Raw. Not saying I don't sometimes do more but those are few and far between. Usually my goal is to learn how to be efficient and quick with it the edits.
Either way I do try to improve my own work overtime. I've seen it grow quite a bit from when I've first started and my goal is to keep growing it.
Part of the reason I would like to compare is it's one of the things that helps keep me going. I like being a little competitive. Don't get me wrong I love doing photography as is, but it's still nice to know where I am in relation to others. Also by doing this comparison it allows me to see what subjects might be selling and allows me to see even if mine are selling maybe they aren't selling as good as others. Then I can go in compare why. Is it the image, is it the keywording and what not.
Let me ask would you handle things different if you found out your portfolio was considered sub par in sales vs if you found out your portfolio was doing above average?