I just saw a magazine article about a double tie breaker. The idea is there are two tie breakers together - one closer to the A side and the other closer to the B side. If you want to perform work on the A side tie, you open the A side main and the B side tie. That way the A side tie breaker is completely dead instead of one side still alive. Anyone here ever use this approach??

Sounds like a good concept but I think this falls under the category of "with enough money you can do anything" a.k.a. extra expense for 2 ties.

I think this was constructed by Powell in Houston, TX but I imagine most switchgear manufacturers could do something similar.

I have used the double tie breaker on some projects, at the time this concept was more for back up, redundancy and or serviceability of critical operations/processes i.e. nuclear, military,chemical plants etc. which resulted in complete duplication of the entire system. and yes it provided the ability to shut down and switch over, keeping operations up and running yet providing the ability to work the "a" side dead. Cost of this type of system is a concern a lot of the time form what i have seen.

That has been around since the 1970's, nothing new. the new scheme is the sparring sub, but even that has been around for 15 years or so.