At least one height observation:
MLB Innings Pitched by Pitcher's Height
And this one for the statistically inclined- I do not number among them -that seems to lend itself to the idea that height does not essentially matter with regard to specific skills. In my quick read of what was apparent, I'm not sure the findings directly assess the idea directly of IP, however, or stamina as the game presents it, and Markus did say there were exceptions. Notice the cutoff he chose was 5'11, just like Pedro, often cited as the poster-child of the short successful starter, so maybe that benchmark isn't without some merit:
http://sabr.org/research/does-pitcher-s-height-matter