[mightybyte]

I would say very often. For an example, let's look at the throat strike. Any time you could plausibly punch someone in the face, it could instead be a throat strike. It takes much less force to end a confrontation with a strike to the throat than it does to the face. This seriously changes the dynamics of the confrontation. This same reasoning also applies pretty well to eye gouges.

Now consider hits to the back of the head. If an MMA fighter exposes the back of his head to you, the quickest way to end it would be a palm strike to the base of the skull: lights out. But because that's illegal fighters will be a lot more likely to go for something like a rear naked choke, taking the fight to the ground and artificially inflating the value of grappling.

And that's just three of the many illegal moves.

[trhway]

> Any time you could plausibly punch someone in the face, it could instead be a throat strike.

not really. If you look at a good boxer during a fight, you'd not see any opening for a throat strike.

Boxing, being one of the most practically efficient techniques at the "upper floor", is perceived and frequently really is missing at the "ground floor" and this is where Muai Thai comes in - basically extending the boxing for hands with the boxing for legs, as out of the many footwork styles - taekwondo, karate, kung-fu - the Muai Thai's footwork is the most similar to the boxing ideology and style.

[S_Daedalus]

That's my impression too. Gouges and the rest can create opening, and they're an edge if you're evenly matched with someone, but in the same way that sharpshooting might. It's a skill, an interesting one, but how often does a fight with pistols come down to really precise aim, rather than hitting the head or center of mass?

I think it's similar in physical combat, although some elements like the dropped elbows and kicking a downed opponent would definitely end a match faster, you have to drop them first.

[gmarx]

Those moves were't illegal (except eye gouge I think) in the early days of UFC and I don't think they decided any fights.

Still, I agree with your point that UFC shows us the best mix of skills for that particular set of constraints, not necessarily for self defense in the outside world.

Also, in sports there is always the occasional surprise new technique that dominates for a while until others train to counter it. In the early days of MMA grappling alone could win, as long as you had a finishing move (which is why early on some of the huge greco roman wrestlers could dominate a match and still lose).

[caminante]

I don't view the unified MMA rules as demonstrative of a technique's effectiveness. The rules were crafted to preserve the longevity of fighter careers. These are trained fighters on an even playing field.

Pulling off eye gouging and throat strikes are low probability and expose a fighter. Bas Rutten has a bit on these techniques, their effectiveness, and how doing either leaves an opening.

[mightybyte]

> Pulling off eye gouging and throat strikes are low probability and expose a fighter.

A throat strike is no lower probability or more exposing than pulling off a punch to the face. It's just a couple inches away...

[caminante]

trhway's comment above is good reading.

To emphasize trhway's dose of reality, here's Bernard Hopkins explaining proper technique with the chin to avoid getting knocked out.[0] Throat punching is hard to pull off because proper defense doesn't allow for it.

[0] https://youtu.be/SHwPBTDDp00?t=3m49s