Uh oh: Why are the Treasury's Prime Dealers Willing to Park Money at 0.145% for 70 Days?

From The MarketTicker:

...Note that the PDs (that's the big banks that deal directly with The Fed) took basically all of the auction, and they were willing to loan all that money to the Treasury at an annual interest rate of 0.145%.

That is essentially zero.

So what is it that these big primary dealers see happening (or more importantly, have been told and thus know will happen) in the next two months that leads them to think parking $22 billion of money with Treasury at zero interest will provide them with the best possible return on their investment? Oh, and they bid for nearly 5x as many bonds as were sold too.....

I know, I know, its "a new bull market", and you should buy stocks, right? We're going to the mooooooon!

Care to re-examine that thesis given that these huge banks, all of whom make a lot of money trading equities (and commodities) are falling all over themselves to park their money with Treasury at zero interest for the next two months?...MORE