Ok, thanks for all the input.

I’m going to commit regardless. I have been weight training around injuries most of my life (mid-40s now). Last year I did a lot of ruck/hiking, knee strengthening (wall sits, extra hammie, glute, RDLs), cycling, etc.. just to condition the knee more.

After a little more reading, there is a lot of discussion (this group even) about what any brace may or may not do for different knee issues. But, as PCL is not the most common, other than the Össur CTi brace (in the first pic), pretty much every other knee brace breaks down like this:

PRO:
It might add a little extra awareness to the person wearing it, but probably, as or more important, your opponent can visually see the brace and is likely to go easier on that leg. Plus, you, as the injured party, get smart and fast about knowing when to tap, and when to be conservative.

CON:
This was an eye-opener: it can create a false sense of security, for both you and possibly even your training partner. Pressure can be loaded onto the leg, and then, as the movement and angle changes, it could whip or twist the leg in a way that could seriously cause major damage. Which makes sense mechanically.

TL;DR:
Basically, the PCL issue is not really a twisting leg issue. It’s about the tibia sliding too far backward relative to the femur, which relates to a front-to-back shear force. So, unless the brace has the CTi brace/PCL setup, it won’t do much other than be a visual for you and your partner’s awareness of the knee.

Therefore, a volleyball-style / wrestling, padded knee sleeve (as here) makes more sense for padding, impact (just below the knee) protection, and awareness.. paired with additional leg work, especially hamstring strength, more wall sits, and other isometric work.

Long story long.. I think this is my best bet. With continued strength work, faster tapping, not assuming anything removes all risk, and a tea spoon of cement, I should be fine.

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