Somehow, I managed to obliterate the original post for this, packed as it was with all kinds of helpful links. I guess I just don't know all the ins and outs of blogger.com
So, here's the Cliff's Notes version:
20-game chart, blue line = runs scored, orange = runs allowed.
The Blue Jays may have given up lots of runs recently, but look at that downward trend in runs scored. That's the real culprit, the sputtering offense.