Tom,

How did the efficient frontier "fail?" It is a tool for rational decision making under uncertainty.

What do you mean by "pillar?" MPT neither depends on CAPM nor implies CAPM's validity.

I can't comment on "EHF" because I'm not familiar with it. Did you mean "EMH?" MPT does not depend on EMH either.

Markowitz 1959 is replete with all kinds of caveats people often don't remember: It allows for using asymetric risk measures. It calls for an experienced practitioner to use judgment when applying MPT. It even has the seeds of behavioral finance. Daniel Kahneman actually credits Markowitz for giving him the idea of loss aversion (see Prospect Theory: An Analysis of Decision under Risk, by Kahneman and Tversky)