Audi and all,
I will get off on some tangents here so forgive me.
I would agree with most of Wushuer's points, esp. about taiji being concerned with ending a confrontation in the least possible amount of time. This the basic strategy of taiji as a martial art.
In the time of Yang LuChan (and before), "self cultivation" in the martial arts was not the big thing, or rather, had a different focus. Not all had the desire to become monks. I would guess that self-cultivation would have more to do with personal "honor" than becoming "one with the Dao". Of course this could change, and often would, as one matured. This would be true then as it is today. In the days of ChengFu the focus changed quite a bit. Some say that this was a "marketing" shift. Some say it was "evolution" or changing times. I tend to think that it was all of the above. Was this a good thing? I don't really know. I guess it depends on what is looking for.
"Lethal/nonlethal" or "injurious/non injurious" application was determined by the conflict. In those challenges Audi refers to, a person with "good sense" is not going to injure the opponent unless necessary. And here I am talking about Non hostile challenges---just someone testing his art. And as Wushuer says, much of that CAN be determined by the amount of force that is delivered to you to "use". Were these "challenges" (hostile or not) or "personal duels" common with taiji practioners As the books and movies say concerning other martial arts---those of Japan or China? I expect it to have been so for awhile anyway. How else did taiji get it's reputation? Why was YLC and his sons asked to teach the imperial guards and the elite? And how did it lose that same reputation? While your "hard styles" continued much of that activity in the back alleys, in the "dojo", and tournaments etc., tai ji "evolved" past that, It was a certain outcome due to aspects of philosphy coupled with "modern" thinking and concerns. Also, why are there not taiji tournaments as one finds in Hard style Kung Fu? Because due to it's nature , the likelihood of serious injuries is very, very great especially with any but the higher level practioners of the art. When such events do take place, the huge number of necessary rules take away most of the martial effectiveness, or rather, the "nature of the art". The attacks on pressure points and the joints are gone. You end up with push hands for the most part with MAYBE some throws. A training routine, not a fuctioning complete martial art. Over time, as taiji became tested less and less it became a joke to the "hard" stylists, thinking push hands was what we call "fighting". I think fewer and fewer, even in the taiji community, understand just how devastating this art is and was designed to be. I find people tend to have rather "romantic" ideas concerning taiji. what is was and is now.
That Daoist and Confucian ideas/ideals (this NOT directed at you Audi) are the overriding principles (and basis) of taiji and the "soft styles". It is true, that they emphasize some aspects strongly, but in the area of actual philosophy taiji is not influenced more than anything else in Chinese culture. The big three Daoism, Buddhism, and "confusionism" are the basis of the entire culture, taiji as well. I would say that in taiji one may find a fuller expression of Chinese culture than one may find in Hung gar for instance. But the aims are the same---to overcome one's opponent.
In a "real" confrontation a successful technique used in the "challenge" that ended with no injurious results would be followed up with a technique that would end it right then and there, or used differently initially. To end a confrontation one must make certain that the other is unwilling or unable to continue. Physical pain is the method applied in the martial arts. There is no getting around that fact. The idea of fustrating the attacker to the extent that he "gives up" is a relatively modern invention in my opinion. It can work if the attacker is not very serious and/or has some sense of self preservation. With those lacking those attributes, say someone on PCP, "fustration" will have the opposite effect. One always has to remember that the longer conflict continues (even verbally) there is the increasing likelihood that you will get hurt, that you will come out on the "losing" side....no matter how good you think you may be, no matter if "right" is on your side. The whole theory of taiji combat seeks to avoid that. He moves, I get there first---it is over.
I would tend to disagree also with the opinion that duels etc were not, nor really the case back in those days (mentioned above). The one thing I know about the Martial arts, esp the "hard styles" is that proving oneself is a big thing with many, many individuals. Some just wish to see how they are progressing, but many (I have met many) just want to show others what tough guys they are. It was no different then as it is now. And in a time when the martial arts had more relative "value", I expect there was even more of it, and maybe even more of the later type. Who would the martial arts attract back then, and why? "I" would not probably have gone to Yang Lu Chan, or a Shaolin teacher for "enlightenment" as my primary reason. How did Yang Luchan promote his "new" "style"? This was shown by defeating opponents. One can't prove your style by having board breaking demos in dangerous times. In some of these I expect there were injuries in others, there were not. One should also remember the "turf wars" between the martial arts schools in the early seventies (late sixties?) in Chicago. Who's school or style was "best", competition for students,.... It didn't just happen in the Kung Fu flicks. I also know from persons in China that in some of the rural areas the thieves and "bandits" carry on just the same as they did in the "good old days" as pverty has not gone away. Life is still "cheap" for many. Those that are preyed upon have no problem in using lethal force either. The local cadre is very capable of overlooking the demise of some neighborhood thug. Yang LuChans home turf (Kwang Ping prefecture) is still known to some, for people who can "fight", not for their high level martial art "skills".
I think it is "best" to understand taiji as a fighting art, designed first and foremost as such. Then to understand it's evolution. So many have lost sight of what it is. Some even think that it never was a martial art. I wonder how one puts "intent" into ones actions if it is only a tool of self-cultivation or achieve better health. Audi, I know that you do not hold this veiw, but some do. I also think that more and more will come to hold that opinion---esp in the Yang style as it becomes more diluted in some schools, with "new agey" mumbo jumbo and extreme pacifism. Don't get me wrong, I am more or less a "pacifist". But as Wushuer says--the one that messes with me and mine (or a defenseless stranger for that matter) had better be "at peace with his gods". Being amplified for effect to some degree, as I know "Wushuer" to be a man of reason and principle---one could envision a serious attack ending with broken bones and maybe some maiming....and I will do my best to make sure it was not me. I know that the "local cadres" here and now, frown highly upon lethal encounters. The factor we face today is if the attacker lives, he'll sue. You had better have witnesses if you ever have to really use taijiquan. It is a sad world.
I expect this is going to need some editing........