Sorry, I should have mentioned I play on a private server.
You can now make a return with this macro, either with LuaPulse (But that implementation seems awfully clunky; I havent used it yet) or a different hack that works exactly like LuaNinja with a plethora of other hacks, but you will have to PM me to get its name.
Also, I have since added a few things to my own arms macro, including sundering and Unrelenting Assault usage against pvp targets (Only casts overpower against a player if casting a spell or close to the overpower buff refreshing). Also will not rend if the enemy is almost dead in a dungeon/raid.