Yes, if you had crit with the normal fists against everything but a heavy (excluding overheal) you could likely kill them in one hit, BUT if it IS a heavy or if it IS an overhealed target that would not die from a single crit, the holiday punch's punch will allow you to kill them with your primary super easily, and if its not an overhealed heavy, or a soldier being healed you can likely finish them off with the holiday punch, AND IT ALSO CRITS FROM THE BACK??? AND IT CAN TAUNT KILL WITH THE MOST RANGE OF ANY OTHER TAUNT KILL IN THE GAME??!?! overpowered. But perhaps the most overpowered mechanic about it is [DRUMROLL PLEASE]....
IT CAN COMPLETELY FUCKING NEGATE UBER. Yes, that is right. If you hit a medic or a pocket while they are ubered and get a crit or hit them from the back they WILL laugh and keep wasting their uber. Not only that but if its a medic and you do this to them they can't switch targets to somebody not laughing (like if you did it to the person being ubered) and you pretty much kill the medic immedietly after they finish uber, even better if they were half way through when they started the taunt because they'll still be taunting when they finish their uber.
So lets review, its the only other melee that can backstab besides spie's knifes. It can completely negate uber (unlike pyro which still has to get within airblast range of a fucking ubered target to push them away, and even then if the pyro doesn't push them far enough they can still use the last remaining bit of uber) which in comp is a REALLY fucking big deal (and get this. UGC hasn't banned it yet because they don't realize its potential so if you main heavy in highlander, you should sacrifice the slow rollout for the ability to basically win the fucking game by completely denying an ubered push.) AND it has he longest taunt kill range of any other weapon in the game which you can aim at somebody and not have the animation look at it. and have you seen the meme potential
Like all jokes aside this is seriously broken at high levels where uber matters, especially if you can manage to sneak behind their medic.
IT CAN COMPLETELY FUCKING NEGATE UBER. Yes, that is right. If you hit a medic or a pocket while they are ubered and get a crit or hit them from the back they WILL laugh and keep wasting their uber. Not only that but if its a medic and you do this to them they can't switch targets to somebody not laughing (like if you did it to the person being ubered) and you pretty much kill the medic immedietly after they finish uber, even better if they were half way through when they started the taunt because they'll still be taunting when they finish their uber.
So lets review, its the only other melee that can backstab besides spie's knifes. It can completely negate uber (unlike pyro which still has to get within airblast range of a fucking ubered target to push them away, and even then if the pyro doesn't push them far enough they can still use the last remaining bit of uber) which in comp is a REALLY fucking big deal (and get this. UGC hasn't banned it yet because they don't realize its potential so if you main heavy in highlander, you should sacrifice the slow rollout for the ability to basically win the fucking game by completely denying an ubered push.) AND it has he longest taunt kill range of any other weapon in the game which you can aim at somebody and not have the animation look at it. and have you seen the meme potential
Like all jokes aside this is seriously broken at high levels where uber matters, especially if you can manage to sneak behind their medic.