It's a bit hard to say, because whoever get initial aggro does most damage on trash packs, but I now have
316m combat logged for Overall Damage all of it in UBRS Rend runs
https://i.imgur.com/Ef59sWE.png
I pretty much draw the same conclusion as you, fury warrs need more management since the warrior will sometimes sit at 100% rage and not have anything to do but wait for execute.
And making a castsequence or the like with heroic strike in there will be even worse damage I think.
If I planned to raid on the warriors which seems unlikely I would try out fury more, but I think i'll stick to arms for now.