I think it's just kind of random and unlucky, but also correlated with the collapse of the offense and the starting pitching, during the slump. Puts more pressure on the relievers, forces them to pitch more innings, and you notice it more when they blow it (plus the offense doesn't bail them out with a comeback or 10th inning win).
I was pretty amazed to see that the team blown save % was 61% and that's about average. Obviously they were above average in the first half of the season. But that still means it is pretty much normal for someone to fail to protect a lead from the 6-8th inning probably 25-30% of the time. You just don't want your closer to do it more than 10-15% of the time.
I also think stability remains underrated. Right now they are both trying to recover from the various individual struggles and trying to reorient everybody's roles, as well as adapt to new team chemistry. They have six weeks to figure it out.
I also wouldn't leave Strahm off the list. He has a 4.76 second-half ERA and his WHIP has jumped from .798 to 1.059 (which, granted, is still good, especially compared to others).
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