I don't think that what they can not use in the cage due to limitations makes them superior in any situation. Kicking somebody in the balls, gauging eyes, breaking fingers all can be also applied by an MMA fighters. Also, if you let the mma fighter know that these techniques are allowed, even if he does not use them, he can easily defend himself against them and still win the fight using, a proper submission, GnP or KO. The "dirty" tricks of many street fighting systems usually work on opponents who are already out on their feet from something else like a broken bottle in the head, or against people who have a very limited knowledge of the fight game and could have been easily defeated using some other technique which is not considered dirty.
Trust me, we can take the best HW Krava-Maga practitioner, let him use the full potential of his techniques, put him against a top 30-50 MMA HW and he will still get destroyed with one of his hands on the HW's balls and the other trying to gauge his eyes
Note: I am not trying to disrespect Krav Maga, I know its effective and there are really solid guys out there, just mixing in some humor

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