I've been using the tandem settings, but what I'm doing requires you to manage your pitching staff on pretty much a daily basis.

I have four starters and a part-time fifth starter. I set them up as the "A" part of a tandem, with a TPC of 90 (they're all in the 80's or higher stamina, 24+ durability) and a MPC of 100. They got 40, 37, 30, 30, and 23 starts, and threw 236, 214, 178, 178, 150 IP. The #3 guy got hurt with 20 games left to play and missed the rest of the season, so he was on track for 35 starts, 200+ IP.

The reason I went to the tandem settings wasn't for the starters, but because I have two workhorse relievers (35/99 and 48/58 stam/dur) who are pretty good and were being grossly underused. I set them up as the B part of the tandem, every other day, with 40 MPC, 40 TPC (lowest you can set on tandem). They do have to rest about every 10th time through the rotation, so when that happens, I just use the top 4 starters as regular starters, rest the two tandem B guys, and use my 3 other relievers, 5th starter in the bullpen in a traditional manner. Those two tandem B guys got in 65+ games, 120+ innings, which I'd rather have than 80 games and 90 IP.

I like doing this, except that I have two pretty good traditional relievers, other than my closer, who get really underused - 33 and 41 IP for the season. Most games my starters (tandem A) were getting me 6 innings, the tandem B guys got me 2 innings, and, if I was winning, the closer finished. So, the other two guys just sat out there in the bullpen.