Part of the reason he tries to squeeze every last out from his starters is that the starters in general have not been going deep enough and the relievers are pitching too many innings.
They are 6th in the majors in runs scored per game, so they are one of the better offenses. Obviously the faults you see in the hitters are shared by most hitters in baseball.
So Giolito doesn't count as 'actual MLB pitching', even though he has excellent numbers on the season, because we scored some runs off him, which proves he wasn't pitching well, because we are s***. That about right?
I think the bottom line is this:
The bullpen has been MEDIOCRE, as expected.
The starting pitching has been unexpectedly BAD.
That's why the pen seems to compare favorably to the starting pitching.
Calling the removal of Johnson after 83 pitches a WTF Cora is pretty ridiculous. The guy started the year in the pen, was on the IL and wasn't ready to be tossing any 100 pitch games.