I've been trying some 6max in the last few days and I feel like cbetting every time can be exploited there more easily, but at full ring 50 it seems to work pretty well.
It is always a tough spot when your cbet gets called or raised and you don't have much, but I think I am profiting anyway with all of the times I have TT or JJ and an A or K flops, I cbet and take the pot. So many people just call with small pocket pairs and then fold when they don't hit.
If you check and they bet because of your weakness, you have to either check/raise, fold, or smooth call and try to take it on the turn. All of these get pretty expensive if you're wrong.
Sklansky tries to balance this with throwing in some check-raise bluffs, but I don't know if people at this level are paying close enough attention to realize you are capable of that and becoming more cautious as a result. I think oftentimes you are just losing control of the hand.
I'd like to hear some contrary explanantions to what I'm thinking, because Sklansky may know a bit more about poker than me. This idea is just in the "concepts" section, so the only explanation offered by him is what I quoted above.