I have agreed that we don't know the real reason this pattern continues at the end of almost all his seasons.
I'm guessing fatigue or endurance or stamina or whatever you want to call it MIGHT BE part of the problem.
Then, I'm making an educated guess that more rest MIGHT help him stay stronger and/or sharper as the season goes along. It's just a guess.
There could be multiple factors.
The velocity charts do not show much of a change, and I agree, it's hard to see any change when watching him do well or poorly. He always looks good, but sometimes he gets hit.
Back to the Velo charts.
Looking at games where his velocity averages 95 or more, he had 2 of his first 14 games below 95. He had 11 of his next 18 below 95 with 2 right at 95.
You might be right though. There may be no correlation. His game 15, 16, 17, 19, 20 and 21 some of his lowest. In those games, he let up these ER in these IP:
3 8.1
1 6.1
0 7.0
0 7.1
0 6.0
0 7.0