I see your point, so you think small caps are going to play catch up? Because I'm not thinking that. If they didn't catch up by now I don't see it happening. Complete laggards! Which mean market participation is completely lopsided!!!
Small caps have under performed the majors for the past 12 months. This isn't a new phenomenon. But from a historical modeling perspective it's probably a good bet to be long Russell 2000 and short S&P 500 or DJ as a weighted spread at some point. The spread could converge even in the face of a broad equity sell-off.