Been answering loads of NLHE questions lately on another forum, and a stnd recommendation I've had has been to use a tool called FlopZilla it's a clever piece of software, anyways I said i was trying to find a post Stu "Honeybadger" Barnett made on the topic because I thought it was amazing, and I found it.
I am very confident Stu would have no problem with me sharing it with you, well worth a read if you're at all interested in game theory, really really good.
about half way down under name "Curry Lover"
http://forumserver.twoplustwo.com/39/small-stakes-pl-nl/nl200-optimal-flop-defending-range-1079282/