Send me a PM if you need help with PVE warrior DPS help- I'll be glad to chat over Skype. Or just add my btag dark#1458
I guess you missed the part where RNG completely decides your TFB stacks, Overpower continual procs, and CS uptime.
Right now you can get between 50-60% BT crit chance as fury, which is statistically less streaky than any of the Arms abilities.
Fury has some degree of synergy between its secondary stats and damage output and get-out-of-jail-free-cards to break bad RNG streaks. Arms does not--abilities either proc or they don't, you have no control over that.
I get that you like Arms, that's great, but let's not be purposefully obtuse when comparing the two specs.
TG is stronger in AOE situations, this has been well documented. The issue then becomes not every fight has adds to AOE, or adds that require sustained AOE. In single-target situations SMF does a lot better....35% buff to all your damage is pretty nuts, and TG having "stronger" weapons with 2H vs. 1H does not compare at all. I feel TG has weaker Rage generation by far, as it gets a lot less normal attacks than SMF.
I did an LFR Terrace with a warrior that had 2 LFR Elegon axes vs. my Normal upgraded Shin'ka and LFR Starshatter....his iLvl below mines by about 10 or so, so by all respects I outgeared him by a fair margin. Despite that in every fight except Sha of Fear he did more damage than I did. That, IMO should never happen but the fact that it did and it does tells me that SMF is just really strong compared to the other specs, and that it needs some re-tuning. After that night I wanted to DE my Shin'ka and cursed myself at A.) taking it away from a DPS that can use it better and B.) feeling largely like I wasted DKP on it. (Now you can make all the derisive comments about how I suck or whatever but I feel like I know how to play the class and role pretty well...not the best but I can hold my own.)
All I can say is test it regarding that choice. I have a feeling the 1H combo will impress more overall....I am pulling more DPS with LFR Kilrak (ungemmed) and LFR Scimitar vs. Normal (gemmed, upgraded) Shin'ka and LFR Starshatter. Double LFR should lose for me, but it doesn't....I am not even in a strong position to win a 1H as our tanks will probably win the next couple that drop, but I don't even care right now. It's hard for me to justify using TG at all if I pull better numbers as SMF with LFR weapons.
This kinda reminds me of 4.2 situation where everyone cried about how Arms is crap right until Enk popped out and started shitting all over everyone. Granted he had heroic Sulfuras but still it was awesome.
That said, Arms does suck and I say it as someone who shelved his warrior a year ago and is looking at friends' and guildies' performance.