It's one area of a few that I strongly disagree with Cora on, but I still really love Cora as our manager. I also don't pretend to know more than him and strongly consider I could be wrong on this and my other differing opinions.
On Yoshida:
1. The whole team had a day off a week ago.
2. He has been DH'd in 3 of the 7 straight days he's played.
3. He has a .937 OPS in those 7 games. (1-4, yesterday does not beg for a day off.)
I'm fine resting players 3-5 games over the season. I'd prefer 2-3, if you can DH a player a few games here and there. I do not think DH'ing is very tiring, at all. In fact, I don't think baseball is tiring all that much, except for pitchers and catchers and maybe busy SSs.
It's just my opinion. I'd still rest players, but I do not think I am mischaracterizing Cora's penchant for resting guys that are hot over their last 4-7 games. Some seem to just be pulling out of a slump, and boom- day off. IMO, players find strides and ride them out. Most players have stat lines that are greatly improved by just a few hot streaks. Don't mess with them.
I still love Cora.