You keep saying "The pen lost games." Sure, the blown saves contributed to the loss, but many times they blew games that the starter had already let up 4 or 5 runs in 3-6 IP. The pen actually let up less runs per inning, but the blown save is blamed for the loss.
On Porcello, it's hard to calculate 10 wins over .500, because the pen numbers would have changed had he not been pulled as early. He's at 14-10, now, so he'd have to be 17-7. The numbers support 3 or 4 more wins (see below), but changing 3 losses to wins would barely change our standing position. (It would change much more, if we look at Sale's starts and losses one-by-one.)
Here are Porcello losses:
IP ER Result
2.2 4 Lost 10-8 (Likely a win, but we may still have lost this one despite scoring 8 runs.)
4.2 7 Lost 15-8 (Probably would have lost had he gone 6 IP with 3 ERs- 4.50 ERA)
4.0 3 Lost 9-5 (Probably still a loss.)
7.0 2 Lost 4-3 (Would have lost by more.)
4.2 5 Lost 5-4 (Probably a win.)
6.0 4 Lost 5-1 (Still a loss.)
Then, the complete meltdown:
6.0 5 Lost 7-5 (50-50 chance)
0.1 6 Lost 17-13 (Hard to know, say 50-50)
5.2 6 Lost 8-5 (Likely a win.)
5.0 5 Lost 12-4 (Likely still a loss)
Porcello won a lot of games despite pitching poorly or awful. I see one game where had he let up 3 ERs in 6.2 IP, instead of 2 (like he did), we might have lost, since we won that game 4-3. That means the net gains of wins might be 2-4 games.
Think about how many games the pen won or held a win for Porcello (and others) or the team. Here are some of Porcello's wins:
IP Runs Result:
6.0 3 Won 7-3 (Pen 3.0 IP 0 ERs)
6.2 4 Won 9-5 (Pen 2.1 IP 1 ER- better ERA than Porcello)
6.2 5 Won 12-5 (Pen 2.1 IP 0 ER)
5.2 6 Won 10-6 (Pen 3.1 IP 0 ER)
5.0 6 Won 17-6 (Pen 4.0 IP 0 ER)
6.0 3 Won 19-3 (Pen 3.0 IP 0 ER)
(Yes, with these many runs scored in support, it is unlikely we'd have lost many of these games had the pen done worse, but the fact is, they did better than Rick in 6 of the 14 wins.)