Cliff Lee has been out-of-his-mind good this season. He's 6-0 with a 0.81 ERA. While it would be extremely unlikely he could continue to pitch this well, I noticed he is relying on his fastball more and change-up less this season. In fact, his pitch breakdown is very similar to 2005 when he went 18-5 with a 3.79 ERA.
Of course there's no way Lee is going to keep stranding 86% of baserunners, but his LD% this season is a career-low 14 and his GB% is a career-high 47. His FB/HR% is 2.2 and BABIP is .216. Lee's BABIP in 2005 was .287, which is a little bit on the lucky side, but not too much.
There's no question Lee's stats will correct themselves to some degree, but if his success is related to returning to a previously successful pitch breakdown, he could be good for the long haul.