Buying at 20.

Quote from candletrader:
In my humble opinion, the only spreads where there is consistent scope to play the mean reversion game is between intramarket spreads (often known as calendar spreads) or inter-exchange spreads (similar markets, different exchanges)... and not spreads between 2 intermarket futures (such as S&P and DJIA)... just my 2 cents, and a highly debatable area...
Quote from daniel_m:
by no "consistent scope" do you mean on a r/r basis? ie spread between nq and es is likely to revert to mean, but playing on that doesn't make much sense sense from r/r perspective?
or do you mean that mean reversion on such a spread isn't likely, or doesn't occur enough? or, perhaps, that such a reversion is only an 'illusion' and that there's no good reason to believe the spread will ever revert?
i don't mean to grill you, but i'm just curious, cos i would have thought that the sp, naz and dow would have been ideal candidates for such plays..