The arms spreadsheet that I created has really been deprecated since 3.0.8; I need to rework it. With Sudden Death changed, theres a lot more that needs to be considered, but my initial work shows:
1) Stay in battle stance, and keep rend up at all times
2) Bladestorm > Execute > Overpower > MS for your cooldowns/jerk reactions
3) Slam only when none of the above 4 is available
4) You should be using an ability EVERY GCD. If everything is on CD, you should slam until something else is available
5) For execute range, if you're bloodlusted/heroism you may be able to spam execute more liberally, but this depends on gear.
1) For bladestorm, there's a sequence you can go in to get the most bang for your buck:
- Execute/MS until your rage is low
- Switch to berserker stance
- Whirlwind if you have the rage and can still pop bladestorm after
- Pop bladestorm
- When bladestorm ends, Execute/MS/WW to get your rage back down
- Switch back to battle stance and refresh rend if necessary
This gives you the extra 3% crit and a shot to whirlwind, with minimum rage loss
2) Glyph of Mortal Strike and Rend. Not sure on the 3rd one with WW changes (I'm fury now).
That's all I have for right now; there's more but as I haven't been arms in 3.0.8 (we have a feral druid and combat rogue, so fury is better for the raid).