I too disagree about the distinction between longevity between MMA and TMA.
MMA is simply a selection of TMA techniques that have been tried and tested under pressure of fully resisting oponents, and taught in synergy to give an artist options in all ranges of combat. Its that simple.
Quite often you will hear the rationale that very experienced TMAists over decades of training, first learn everything in their system, then spend their training distilling that system into the purity of what works for them. It is almost a deconstruction where they come to the emlightenment of the power of the truth in the 'basics'.
All MMA does is streamline that process by cutting away the flab and teaching people to rely on solid basics from day one, and teaching them to function when under genuine pressure of a real oponent.
If anything, its closer to the roots of TMA than the hundreds of layers of codified complications that came about in the centuries of peace-time tinkering with the arts.
I'm late to the party folks, but this was very well-put by Cord (as always)! While risking that I may be repeating what someone else has already offered, I'd like to add that MMA training is perfect for the development of tested technique against resistance.
However I do see a few minor problems with taking the MMA approach for self-preservation.
1) Quality of coaching and knuckle-dragging partners who have little regard for your health.
2) People who are unsavory characters. They'll let ANYONE into many of these gyms. You are who you train with.
3) Lack of strategic training. MMA strategy of always moving forward, always seeking clinch or ground, is NOT always the most intelligent path.
What is needed is a tweaking of the TMA and/or Combatives training processes to make them more athletic and resistive. Their strategies are often more relevant to SD. The training methods are sometimes lacking.
Different situations call for different strategies. If you're don't allow for weapons, more than one attacker, or the use of "foul zone" attacks, you're short-changing yourself (IMO).
In other words, a meeting in the middle between TMA and MMA is needed.