this late stage buying is probably those who think that the market downturn has reached its bottom. Eh, IMHO, no.
Too many issues to deal w/, the deficits, the weakening of the economy in various areas (manufacturing is sluggish, the services industry is now slowing down), pathetic rump attempts to drive imports/exports as a means of driving agreements (which doesn't work), interest rates are always historically low, so if any impact from reducing the interest rate paid by bankers would be minimum. Inflation rates are creeping up too, probably as a result of too much money chasing after too few quality assets. A sign of perhaps a bubble economy?
Unemployment is already at its lowest in a while, and basically, any new economic expansion would need a revamping of the labor force (to make more efficient so more can be done w/ the existing labor pool), since immigration as a tool to bring in laborers is pretty well shot...if you don't believe me here, ask the farmers who've had to leave crops in the fields to rot, since they couldn't get workers to pick/harvest their crops. Farmers and/or ranchers have already been suffering quite a bit over recent years for record low prices for their harvests.
Like the late 1920s - early 1930s (the depression era), efforts were made then to attempt to drive the markets into positive areas by buying tons of securities in an effort to stem the downfall. It didn't work, and I suspect that it won't work too well here, being that there are too many negatives, too much is already invested in the markets as they are now (an oversized asset bubble) and there is a natural inclination that bubbles eventually resize themselves to the reality of the marketplace.