Here's a very important point to remember---two points, in fact: the type of pitcher you are and the height of the mound. The Yankees were playing the Royals in Kansas City, and Chien-Ming Wang was on the mound, and he was having some trouble. Jorge Posada called time, came out to the mound, and told Wang to shorten his stride. The reason for this was that Wang is a sinkerball pitcher, and the mound at Kauffman Stadium is lower and flatter than at any other ballpark in the majors---disaster for sinkerballers! So Wang shortened his stride, and he went on to pitch seven strong innings and get the win.
So check with your catcher and check the mound, and adjust accordingly.