Running a repeat of an ongoing series on its usual night and time when viewers are expecting a new ep is usually a bad idea as it runs the viewer base off, thinking the series is on hiatus.
That’s true and I think it is the reason Chase got dropped.
I just read this at http://insidetv.ew.com/2011/10/28/blue-bloods-world-series/:
CBS is outta here. With the World Series going into a seventh game tonight, CBS is pulling its original episodes of CSI: NY, Blue Bloods and — brace yourself — A Gifted Man. Repeats will air instead — the Gifted Man pilot, then encores of CSI: NY and CSI: Miami (no Blue Bloods).
Your right about their explanation for why. Now we’ll see if they run it next week.