I admit i may be wrong after reading that NCOP section.

The part about early versions prone to failure make it sound as though once upon a time they weren't allowed.

I was under the impression they weren't allowed, not because of poor lifespan, but the ability for them to be installed incorrectly which would be a very bad thing.

But it sounds like maybe you are allowed rose joints, provided they are installed correctly and that someone official says it's alright