I don't think MacPhail really preaches grow your own pitchers. That is something he said years ago, possibly with the Twins, that the media really picked up on. What he preached was basically the same as Gillick, don't sign FA pitchers for more than three years, so I suspect he's as much responsible as Klentak for avoiding Corbin (as if 6 years is that much worse than 5, which is what they offered).
Beyond that, if MacPhail believes you should grow pitchers but the team isn't drafting them that merely serves to remind that he is not running baseball operations, it is merely one thing he oversees. He may actually have less influence on Klentak than Monty did on Amaro (but Amaro only got the job because he was an organization man).
These are supposed to be competent new school people, Kapler even more than Klentak given his Rays/Maddon/Friedman/Dodgers pedigree. Perhaps MacPhail believed in Klentak, his guy from Baltimore, who really didn't do anything else of distinction except watch Jerrry DiPoto get fired, too much. I think a lot of the problems still trace back to the extremely slow timeline, both in hiring a GM (Milwaukee got theirs from Houston months before the Phillies even started doing interviews) and overhauling the organization.
I'm not willing to draw too many conclusions from two different seasons of collapse, circumstances were very different. Last year the team caught up to its actual talent level, I'd say. this year its talent level has cratered (both due to injury and performance).
Hey, what can we get for Neris now?