Yeah. Maybe. So the point they are making is "top guilds account share all the time and nothing happens"?
That screenie was from Emerald Nightmare and there's been plenty of World Firsts ever since? All of the "world first" guilds take calculated risks around account sharing, and Blizzard's lottery banning wheel doesn't seem to care much.
¯\_(ツ)_/¯
Judging by their post history, I think the purpose was just to kick up some nerd outrage in forums, but idk.
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The playtesters and players are often the same people.
The top guilds playtest these things during betas.
Sometimes (for a player) it's hard to know if something is intended or not. Sometimes it's impossible for testers to catch all use-cases players are going to try. These things happen. Blizzard spins the wheel and sometimes people get banned. Often they don't.
Blizzard doesn't really communicate as much as everyone seems to think they do. Especially not with EU guilds. Method doesn't have a red phoneline to the designers (some of the people in Limit do have personal connections though). But generally, Blizzard keeps the door to the ivory tower locked and watches from the balcony.