Lemme quote a guy.
Quote:
It's not cheating, though. It's a flaw in the game itself. It's Blizzard's fault.
In video games -- excepting shitty ones -- the rules are not written in a book that players have to read before playing. The rules are defined by the way the game is programmed. If you can do something in a game, it's within the rules, the only exceptions being the exploitation of obvious glitches (e.g., finding a way to walk through walls in a first-person shooter). There is no glitch in this case because the abilities were working as intended; the fact that Blizzard didn't foresee the use of this particular strategy does not mean there was an error in the code.
In Magic: The Gathering, there are plenty of cards that get banned from certain formats, but using them before they are banned is certainly not cheating. Furthermore, using a particular combination of cards that results in an instant win is not cheating, even if no one at Wizards of the Coast ever thought of that particular strategy. The player is not limited to combos that have been pre-approved by the game's designers. The rules are all written, and looking at those rules to find the best way to win is legitimate. In the case of video games, the "rules" are written in code, and carefully studying these "rules" to find the best strategy is not cheating unless you hack the program or do something that is otherwise not explicitly or implicitly allowed.
All four players on a team using the same ability on the same character is not a cheat.