While cauterizing a flesh wound perhaps, I don't think it would stop death from severed arteries, so still semi-awesome as a sword.
However, the flaming nature of the weapon adds new uses.
It can be used as a torch to light your way at night as you charge into battle, or flee from the enemy.
It can be used to torch a village as you ride through homes with thatched roofs, or you could set your enemy on fire with it. Hard to fight back when you're on fire you know.
You can signal your forces with it at night from a mountain top or other high place. No more bonfires required.
It can be used to warm the body, and cook meals on the battlefield, boil water, etc.
And when the war is over, you can use it to brand your cattle back home, and dry your tobacco leaves so you ca treat your sick cattle and bruises.
Plus, it looks really cool, so it has the shock and awe value going for it.
So...different? Yes. Less awesome? No way! Imagine the estimate if that thing ever came up on Antiques Roadshow!!
it's usually accomplished by way of a flaming sword. But angels have other ways of torching their targets. There's the "Breath of Death" which is more of a caustic chemical burn. But the result is usually the same...a charcoal briquette that was once a human being.
The angel that commanded Joseph Smith, Jr. to have sex with various women chose to turn off the flame before showing the sword. There was some concern that Joe's priesthood could get burnt by accident...and that would have frustrated God's purpose which was for Joe to share his priesthood with as many women as possible.
There was reportedly an angel using a flaming sword at the entrance to the Garden of Eden. According to the story, after Adam and Eve were kicked out of the Garden of Eden Spa and Resort, they tried to sneak back in, but found their way blocked by an angel wielding a flaming sword. But experts and academicians generally agree that it was more likely flaming sticks being twirled by "fire dancers" in a Tiki show that was being put on for a special luau inside the Garden. Adam and Eve only saw it from a distance and assumed the worst because their expulsion from the resort had shaken their confidence and given them a form of PTSD.