Hi,
This is really not an easy question to answer, I'm afraid Black Lion. While I appreciate the answer you gave, you missed a major part of the question, which MJS cunningly hid in the thread title. The full question is "How well do you feel that ring fighting prepares you for a confrontation in the real world?" And that opens itself up to many other questions, most obviously "what kind of confrontation?"
But before I get to that, I would like to cover a little more ground first. We have established that what we are talking about is MMA-style ring fighting (I'm noting that this is distinct from the training itself, but I feel that the two go together... after all, someone is not likely to enter an MMA bout without having some training in preparation, so I'll mention that as well), so we'll examine that a bit first.
When it comes to MMA-style competition, there are some very substancial differences between it and a real violent encounter, leading to very different training methods, and both having very different aims. That obviously then leads to certain approaches, strategies, and tactics that are geared up towards success in the ring, rather than in a self defence situation. This, of course, doesn't mean that they cannot work in an SD situation, just that that is not what they are geared for.
These include, but are not limited to, working within a specific rule-set (which can train you to miss certain openings, or look for inappropriate actions/techniques), training for long engagements (multiple rounds, which can lead to an expectation of having time to establish rhythms,, wear someone down etc, with the focus of a single opponent), looking for "scoring" techniques (knockouts, submissions, point-scoring kicks and strikes, lending to the tactic of wanting to stay engaged in a situation, rather than looking for the option of an escape), and the obvious expectation of a single opponent, well trained in a similar skill set to the one you have trained in and are using, with the opponent similarly limited.
The more the training is geared towards competition, the further away from self defence it will be. The techniques may be able to be utilised, but the training will dictate the response you experience under pressure. And, while the techniques may indeed be highly effective, the tactics may be not ideal, and could limit the effectiveness of the techniques themselves.
To show what I mean by that, we'll go through the way both an MMA fight happens, and a violent assault (in this case, just a random drunken situation at a bar).
An MMA fight and a SD encounter have very different timetables. The timetable for MMA involves a period of time general preparation (regular training in a range of skills suited to the environment expected, a competitve encounter with specific rules and expected technical considerations), and then a period of specific preparation (usually geared towards a certain known opponent, who's approach, tactics, methods, and preferences can be studied and prepared for). When it comes to the fight itself, the timing is pre-determined (you know when it will start, and where, and against who), and you usually get a certain amount of time for the pre-fight (during which you can mentally and emotionally prepare, as well as physically, and could be half an hour or more), then the fight itself, which is typically also determined in length (say, 3 x 5 minute rounds), and then there is a managed post-fight (with the physical and mental aspects often managed by people around you). Finally, there is the ability to then rest, taking time off training, as you will know if you have another fight coming up, and when it is, so you can determine how long to take off.
An SD encounter, on the other hand, if we assume training (hey, it is a martial arts forum....), then there is any amount of time for general preparation (ideally covering far greater range than the limited aspects of any competitive system, including escape tactics and more), which could be anything from a few minutes to years, or decades. Specialist preparation is usually no more than you simply seeing the guy get angry, or maybe noticing a few pre-fight triggers (if you are lucky...), and that obviously also covers the pre-fight. The duration of the encounter is unknown, as are a large number of other aspects, such as number of people, weapons, aspects of the environment (unless you are there very frequently), and more. And the post fight is rarely managed in any way, you may be injured, you will certainly experience the drain of the post-adrenal dump, during which it is entirely possible that you will be attacked again. And as you never really know when this could happen, you should prepare for it again as soon as you are healed enough to.
And the question of what type of encounter you will experience still needs to be addressed. All we have is "a confrontation in the real world", which could be anything from the aforementioned drunken assault, through to a mugging, through to road rage, to an attempted rape, to simple raised tempers which can be verbally defused. Each of these require a different responce, and with some of them the hardwired MMA response is, well, irresponsible. The need to stay and engage is not advised, knocking out someone who is yelling but not attacking (if they don't show signs of escalating) can be assault, a mugging, particularly if weapons or groups are involved, can be handled by complying, which can be the smarter way to go (let go of ego there...).
Physically, an MMA-style experience, if the base of your understanding of a fight, will lead you to expect a much bigger opening distance than you will often encounter in an assault, as well as only expecting a single opponent with no weapons (at the least unconsciously, as that will be what you will have taught yourself to expect). So you may think that it is not really helpful at all. However, it has a number of things going for it. Many have already mentioned the experience of being able to give and recieve a hit, and this really shouldn't be underestimated, however there is a far more powerful preparation that MMA gives you. Confidence in a physically violent encounter.
One of the big advantages a street predator has is that they are often experienced in hurting people, or at least having people scared of them, and that gives them the confidence to "ply their trade", as it were. So one of the best ways to be prepared to handle such an encounter is simply to be confident in your own abilities to handle it, and the constant testing of technique and ability in the ring that MMA competitors go through instills that confidence, often in spades. So although the tactics are not ideal, and the techniques may in some situations be ill-advised, the confidence in self that it supplies cannot be discounted. And in that regard it can help prepare you for a real world confrontation very well. Just try to make sure that you don't overstep the situation as required...
Phew, that was a long one....