Bear in mind that the Chinese are notorious for withholding vital information - even amongst themselves.

What good is martial application of technique if you don't have the basics that Bossman has already mentioned? Taiji is also a very subtle art (particularly small frame), requiring great sensitivity to your opponent's energy pathways and body alignment. If you do not have the foundational mechanics, how can you ever know it to be anything other than ineffective?

There aren't enough good schools/teachers out there who are qualified to teach the true martial side of Taiji. But from mym experience, Taiji is a base to build on, or to add to a base for martial arts. Because of it, fighting, or even using specific applications becomes almost meaningless because you can knock, or throw people over so easily. All the basic things, although push hands is also something you need (weird he doesn't teach it), that you are doing, are all your going to need in the future.

Do your rsearch if you want to learn more apps etc.

I think there are a couple of Tai Chi instructors in my area, and I might have to look into it as a compromise between not aggravating current problems and staying in MA.
The health type Tai Chi is pretty much what I'm stuck with though.

Of course, some styles like Taoist Tai Chi stress that they are not to be used for SD and it is taught only for health. It was still useful doing it, as it taught me new ways to move my body.This was useful when I finally found a Chen sifu.

My school trains in Chen style T'ai Chi and it is equivalent to very high level Kung Fu. It can be excellent for self defense after several years of development. In fact we think of our training this way. Where you begin training in T'ai Chi is where you should end up in Kung Fu and where you begin in Kung Fu you should end in T'ai Chi. Sorry if that's cryptic but I'm sure long time practitioners will understand.

I also train in Chen Taiji, although its been a few months for me. The best thing about Taiji, is it teaches you how to move your body the right, and natural way, as well as being able to generate alot of power with minimum effort.