In 1910 it was "only a fool uses his best stuff except when he really needs it, because you have to go nine every 3-4 days. Or more."
Today it's "use your best stuff all the time, or you're going to get the crap knocked out of you. But we'll yank you after five innings, and you only pitch once every five or six days."
Overall I'm not sure there's a lot of difference in how long a pitcher lasts.
Or... on smaller time scales Palmer vs Mussina. Four-man rotation and some high-pitch games and high-inning seasons, vs. never topping 250 innings in a five-man and more pitch counts. Palmer threw a few more career innings, but Mussina had three more seasons of 150+ innings. Mussina was never really injured, Palmer missed part or all of four years. And they had almost identical career W/L records.
One thing I remember vividly about McDonald is that the Orioles took away his out pitch(forkball) straight out of the gate. They thought he could prolong his career by not throwing it. Which always brings me to the question. Is it better to burn out or fade away?