No, you still fell cleave a bit even outside of IR so that wouldn't help at all. All the other tanks besides WAR have optimal options to hit 2 targets with some kind of AoE and gain damage. WAR can't do that, none of its skills is a gain on damage on two targets over single target until 3 targets are in place.
WAR has a design issue that steems from the IR change, instead they should revert the change from SB by removing the guarenteed DH/CRT aspect of IR but bring back beserk for a 20% DPS gain. Maybe keep the chaos skills as DH/CRIT but they need something better to help balance their down time without IR. As some WARs point out, there is a fairly massive damage difference between killing a boss before an IR and afterwards.
Because WAR is so darn spikey it puts more pressure on DPS to go out of their way to help more in Ultimate due to the requirement of not having IR when the hand/LL split. You only get to IR again during Protean Wave 2, which is almost at the end of the entire LL phase.
This is the one of the design issues with making a burst tank instead of a consistant damage tank. Sure bursts are important, but when you are all in on your burst there are legitamate issues with that. DRK is also a burst tank, but its burst isn't as high as WAR so it has room to have a better outside of burst damage so you aren't completely 100% reliant on that burst. PLD/GNB have burst phases but they aren't massive but are enough to keep their numbers basically static through out the fight. Again, this issue glares its ugly head in TEA, but one could argue it also comes up when mechanics line up with you are supposed to be bursting that force you to move. Delaying a burst and missing party buffs can lead to missing an entire burst phase in the long run which just extends the DPS difference between tanks.
A rework to reduce burst but improve on its outside burst is needed for WAR, at least in my opinion.