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Years ago, when the Twins traded Ynoa to the Braves, I talked with a Twins contact that said that Ynoa had six MLB-capable pitches, but that the problem is that he knew it. The Twins were working on getting him to focus on three and then letting him bring in a fourth.
I've always felt that a big part of his control/command stuff is simply a feeling in the back of his mind that Ynoa could pull out a different pitch in a different situation, but that he feels like he has to stick with certain pitches.
One reason I had Ynoa ranked #11 in my offseason Braves list ahead of a number of very talented Braves arms was in part that he was given a green light at the end of the minor league season to pitch with whatever he wanted. Most will miss things due to his ERA...
...but Ynoa was SO much more comfortable on the mound, struck out more than a batter per inning, and for a guy who had control/command issues in his background, he walked 7.1% of hitters, a very manageable number.
