The glass is half-full....

No, it's not. Mark routinely threw 89-91 five years ago. Now his four-seamer is more like 87-89. The year after the WS, it was more like 86. That's what age and heavy use do to a pitcher's arm. And while I won't argue that Mark's going to tear his labrum or rotator cuff any time soon, the risk obviously increases with increased use. And even if we accept the premise that Mark is the next Tom Glavine and his arm troubles won't manifest until his 40's, his arm strength and durability will, at best, diminish slightly as he approaches his mid-30s. Since it's unlikely that his command will improve significantly over that time (it can't get much better than it already is), it's difficult for me to believe that he's going to pitch any better than he has over the past three years. So we're looking at either more of the average of the past few years or a slight decline. And that's a best-case scenario.