Since you put it that way?
EMT is a crap theory in the manner it is explained by its critics, which from what I have read, is highly distorted. From the critics you'd think it was an effort to create some sort of deterministic model of the markets. I don't get that at all. From my reading, it is not intended to be an effort to rationalize the markets, more the opposite. The concept that markets price in all that is known about a given stock seems intuitively obvious to me, provided you add, felt, predicted, and suspected. If the current price is not a reflection of all these elements at the current moment, then on what is it based? The critics of EMT can't seem to answer that question, not that I've heard. EMT isn't an attempt to model the future so much as it's an admission that this cannot be done.
Value investment gurus tell us that they can read things into stock pricing that others cannot. If they say a company is undervalued, then it is, even if the rest of the market doesn't see the same thing, or never does. If an "undervalued" company remains undervalued for years, then is it still undervalued? Is the value investor still right? According to whom? In my book they are only right if the markets ultimately see what they saw first. And unless you are Warren Buffett, good luck with that.
The problem with actively managed mutual funds isn't that they adhere to arbitrary rules, but in fact that they adhere to no rules at all. You will find that most of them style drift with abandon. You think you invested in small company growth, but is that what the fund is buying? Often a third or more of the actual investments at any given moment are in something else. Your investment goals are confounded by fund managers who chase trends -- for which you pay them.
It is always possible to outperform. Anything being possible, that isn't the question. The question is whether it is probable.