Merrill Lynch economist David Rosenberg, one of the best in the business, left the firm last week in the wake of its acquisition by Bank of America. He posted one last commentary on Thursday, and, typical of Rosenberg the past few years, it's not very optimistic. Henry Blodget has some Rosenberg prose:

This is a bear market rally that may have run its course. The investing public is still holding tightly to their long-term resolve, but much of the buying power at the institutional level seems to have largely run its course, in our view. That leaves us with the opinion, as tenuous as it seems in the face of this market melt-up, that this is indeed a bear market rally and one that may well have run its course. We have “round-tripped” from the beginning of the year and there is real excitement in the air about how these last nine weeks represent evidence that the economy will begin expanding sometime in the second half of the year.

Growth pickup will likely prove transitory While it is likely that headline GDP will improve as inventory withdrawal subsides and fiscal policy stimulus kicks in, our view is that whatever growth pickup we will see will prove to be as transitory as it was in 2002, when under similar conditions the market ultimately succumbed to a very disappointing limping post-recession recovery. So yes, there may well be some improvement in the GDP data, but it is based largely on transitory factors. We strongly believe it is premature to totally rule out the end of the vicious cycle of real estate deflation – residential and now commercial – that we have been experiencing since 2007. Balance sheet compression in the household sector will continue to pressure the personal savings rate higher at the expense of discretionary consumer spending. This is a secular development, meaning that we expect it will last several more years.

Chances of a re-test of the March lows are non-trivial. To reiterate, it seems to us likely that the risk in the market is actually higher today than it was back at the same price points in early January,