This is the key word. Multiboxing doesnt use automation. It is allowing you to press a button in one instance of a game and mirror it in other instances of a game. Think if you have 2 Word documents open and if you spelled out a name it would duplicate the exact message on the 2nd one. Multiboxers use macros to control the other accounts. This is built into the game and is perfectly legit. Some software allow users to macro some button presses to translate into other button presses. This is also perfectly fine. Lets pretend you have no hands. Now you use a specific device that allows you to play with your mouth. This translates specific commands into controls for the game. wowhead (.) com/news=316475/interview-with-sebens-12-12-mythic-tank-who-plays-warcraft-with-no-hands
So this person isnt allowed to play under your assumption that software that allows translations of commands into a game client. This is esentially the same as multiboxing software as its translating key commands into a game instance or multiple game instances.
tldr: Multibosing is not “gameplay automation” and is only duplicating key presses into multiple clients.