This I can tell you with first hand experience.
Reds development philosophy has been to get upside arms and then.
1 - Tell them to throw strikes down the middle ( reduce walks and missing spot ‘middle “ might paint the black”
2 - Quota on offspeed speaches
Pitches not matter what needs to be fixed.
3 - Baby sit them and move them along as openings arise .
4 - once they get closer promote on need and merit.
5 - important guys reach the Majors not know how to pitch to major league hitters, nor do they have the pitches ready do do so so they either over throw, pitch away from contact (Walks) Once forced to pitch down the middle (Then HR start ) and everyone says he is a AAAA pitcher.
They then get moved to the bullpen or are sent walking.
Amir never had a chance, Romano and many others the same. The workers away from the Reds that find their own development people start making those changes and transform into something.
Not many have what it takes upstairs this can also be taught but rough road if just baby sat.
Note: AAA is used for final Merit but is the most important development stage but not being used as such (This is where the last failure nails their destiny.
I will use Tyler Mahle as example
Lower levels - Fastball only with command that put him ahead of most others. No hitter and was asked why no off speed “Answer was they could not hit my fastball” Result based but not getting better.
AA - Only worked lower Zone and as soon as hitters figured it out started slapping outside corner into right field.
Offseason I told him to work all 4 quadrants and thats when he got to work with Mesoraco (Spelling) this was when his fastball with Command made easy work of AA hitters (Still all Fastballs and horrible Secondary pitches)
On to AAA - Lived off plus Fastball command and no off speed. Coaching reports said working on off speed but he said that was not true. He could still get away with mixing speeds with his 4 seam .
What was missing besides lack of good coaching. He should have been told forget results and use 80% Secondary.
AAA is also not any indication because the only place to practice pitching is in the majors and that starts about 1 to 2 months into the season.
Tyler goes to the majors - Rookie year is dominating first half Fastball only because of same (Mix speeds and move up and down) Command of 4 seam . He then had shoulder strain which nobody was told (Velocity went down and command was gone) Coaching “Interim” just sent him down and you guys said all kinds of misinformed stuff. Because you don’t know.
AAA at 85 and he dominated hurt, this caused a other muscles to compensate and additional injuries. They could have finished him.
He finally on his own knew that he had to add Secondary and has work hard. Splitter for changeup and now cutter and refining slider. Still a work in progress but all should have started in AAA.
When you see his pitch count blow up early it’s because his 4 seem is so hard on hitters but once gets 2 k’s does not have a KKK pitch same goes early 4 seem is too strong to get balls put in play.
Even though baseball today if a pitcher keeps team in game through 5 he did his job. He is just about ready with Secondary to control this part of the game.
I know I talked about Tyler Mahle but he is my best example of failed minor league development and guys being forced to figure it out in front of fans in the majors where there is no room to work on things. Between games is only recovery and arm care.
Extra days do give a bullpen day but also increase chance of injury along with loss of rhythm.