As far as I can remember they are actually a pretty new concept that came about during the dark ages when we started throwing TPE at activity issues out of desperation. We had various types of things before then like team PT’s and stuff but nothing has ever really stuck, mostly because coming up with ideas constantly is exhausting, especially when you need to make sure that it works for GFX as well.
I also could 100% be remembering wrong, I’m ancient and frail.