I hear what you're saying, and I remember those days too, but the game has changed. 4-man rotations have become 5-man rotations; pitching has become more specialized (closer, lefthanded setup, righthanded setup, 7th inning guy, LOOGY, etc.) There is also greater emphasis on how hard you throw, which wears out an arm quicker. Add in the DH in the American League and having bench subs available became less important. I don't think any of this is going to change - teams started doing it because it helped them win ballgames. Any team going back to the old school probably won't be competitive, not over the course of a whole season.