According to CNN (tv, no link, sorry). He says it has nothing to do with Tenet's resignation, that it's something he's been planning to do for a long time. Hands up, all those who believe him.
Now, to avoid the one-liner diary rule (and because it was the first thing that came to mind when I heard this), I leave you with these ever-more-apt words from Yeats:
Turning and turning in the widening gyre
The falcon cannot hear the falconer
Things fall apart, the center cannot hold...