well isn't thursday before options expiration usually a good day for one of those sharp turnarounds, followed by a strong rally in the (late) afternoon?
I agree with you, it is a possibility, but I don't think that dow "need" to correct as much as the Naz, it really did not advance that much, the Naz almost doubled from its October 2002 low, the Dow far from it.
a lot of buying was going on last feb some of the dow components were getting bought at wedgie bottoms so we may be seeing a lot of tax selling, and locking in the capial gains low tax, which may be slated to get removed, fueling the massacre. there were rolling lows in feb and march and april last year