The SOM model is a bit outdated in this regard. In the years 2012-2014, the leaders in Games Started for actual MLB regular seasons were tied at 34. In 2011, two starters actually lead MLB with 35 games started.
True, SOM is outdated. This said, the reason why pitchers top at 34 games is not only because teams have 5-men rotation, but because managers multiply the extra days of rest. I wonder actually if we're not heading in the direction of the Japan leagues where pitchers now have 5 days of rest.
King Felix is one of the pitcher who started 34 games. I just looked at the 2014 Mariners calendar. I lost count but King F. had about 14 extra days of rest, 3 of which were "forced" (no game scheduled after four days of rest). So there were 10-11 days where King F. was fresh, and a game was scheduled, and yet he did not pitch. He even got a start after 6 days of rest even though a game was scheduled after a 4-day rest. That's easily two starts from King Felix that the Mariners lost.
Moreover, there is enough flexibility in the calendar so that if a coach could squeeze in only one start at 3 days of rest before all-star and one after the all-star break, if those starts are carefully selected in the calendar, you could get another 2-3 extra starts.
So, even with 5-men rotation, you could manage the calendar to get at least 36 starts, and up to 38 starts with some creativity.