Everyone knows I don’t work there so I don’t have more info. The policy linked is all they will say about it. They are deliberately vague. Some of the WoW players have tried getting public comments on it this week to no avail.
I would just plan to play it safe. You can run two instances of the game. Just don’t use anything to mirror movements and commands between the two game windows (hardware or software). Stick to manually muling the two accounts and such.
If someone wants to push boundaries in D2R - they can, but it does put their account at risk when they decide to see what Blizz will tolerate.
I personally would rather people be more careful than to mislead and have someone lose an account. So yeah, I am the super careful voice of caution.