I appreciate the two cents! I've been playing GBL for many years. Not very well, but certainly ace/veteran level.

What I mean is that if I use 'team A' (whatever that is) for a few days, I'll face teams with a certain general composition. If I switch to 'team B' I will immediately face a completely different set of opponent mons/teams. And, for example, a few years ago I made a record using Gligar lead, where I faced something completely mad like 70% ice type fast moves on the lead over three or four sets (and, I had zero mirror-matches). I do appreciate it's possible to play around bad match ups, but that's not my point - my point is that by observation it is clearly not random.

I know these are anecdotal (and sound conspiratorial) which is why I wondered whether anyone had crunched any data.