One example (Yang-style tai chi): https://www.youtube.com/watch?v=kp2jWeaKrqI
One example (Yang-style tai chi): https://www.youtube.com/watch?v=kp2jWeaKrqI
https://www.youtube.com/watch?v=7D5DGpORANE
I think that's a pretty good example of what "people who can actually fight well use tai chi techniques" looks like. A lot of force is going into those throws, bodies are flying, and they aren't students doing a demonstration for a crowd. Legit.
He is indeed excellent, but if that is the level it takes to use Taiji in practice, you won't find many people in the world who can.
If it's just about learning how to fight really really fast the WW2 combatives courses seem to be the best available system. I don't think any martial art is suited to the speed and directness of modern life.
I've never fought anyone, but as I've been taught the moves in Tai Chi's martial technique are generally intended to put people down quickly and hard by doing things like breaking elbows, eye gouges, and other grappling intended to severely injure the other party, essentially breaking every MMA rule that would get you disqualified.
This all varies significantly depending on the teacher, my teacher studied Chinese grappling, Mongolian wrestling, Aikido, and other arts that I'm sure he brought elements in from.