The old adage is that great pitching wins in the playoffs, its not always the case. The braves with the 3 HOF won 1 world series, the Oakland A's trio never won it, the Phillies after adding Cliff Lee and Roy Halladay, and Roy Oswalt never won it either. The Astros didnt even have a pen last year Ken Giles was their closer last year lol, of course a rotation that added Gerritt Cole came apart in the ALCS not a single starter other then Verlander could go 5 innings.
It doesn't even matter that Chris Sale hasn't pitched great, all the starting pitching needs to do is not suck, the Sox pen has looked much better adding the starting pitchers to the pen has made the bridge to Kimbrel easier, Barnes has looked very good and Brasier is their most consistent reliever, Kimbrel looked shaky but appears to have fixed his mechanical flaw. Notice the Sox always get on the board first and almost always score whenever another team scores, never letting the other team claim any momentum.