Many battles in Russia were hand-to-hand. In NW Europe, 'Hackett's Hollow' at Arnhem comes to mind.....
I'd say that on the whole, the Pacific had any more hand to hand combat than any other theater. The Battle for Saipan comes to mind where the largest banzai charge of the war took place on 7 JULY. In Normandy, Lt. Col. Cole led a battalion of paratroopers in a bayonet charge--an action for which he would later be awarded the Medal of Honor.
In the ETO bayonets caused less than 1% of ground casualties. Even in the Pacific the casuality rate was equally low. The bayonet as a weapon was far more a psychological one than an effective one. In close quarters the prefered weapons were generally seen as the submachinegun and grenade. Clearing buildings by late war, at least with the US, was based on the use of lots of explosives (grenades) and gratitious firepower. That is throw a grenade into the room to be cleared and then step in right after it detonates and spray the contents with a submachinegun. Use of bazookas and grenade launchers to fire through windows was a recommended tactic. Many units replaced the Mk II "Pinapple" grenade with a 60mm mortar round on their rifle grenade launchers to add more bang in urban fighting.
I would see why that would be. Bayonettes were great when you had one shot and nothing else and needed something to extend your lethal reach. In a modern battlefield (WWII is a modern war), why use an upclose and personal weapon when you can keep and kill your enemy at a distance, where it is much safer for you. Bayonettes do look forboding when marching through broad avenues in the effort to impress the unarmed, servile locals.
My Grandfather used a spearbamboo he still managed to kill 20-30 allied troops in first day Battle of Soerabaya!!
Caught in a suprise attack I can see some Dutch or Japanese soldiers rendered at a disadvantage by a skilled spear carrier. Using a bayonet on a rifle takes more than a little training, for anything other than riot control. Iroh did not give the year. Perhaps this was in the days of muskets or single shot rifles. Or the enemy were some sort of poorly trained conscripts or gendmere types who were not used to serious combat.
Much like a last resort weapon and a way to go out fighting, but my understanding is that the spade was a weapon of choice in the Eastern Front.
At school, I had a teacher who was a Royal Marine Commando in WW2 and he told me that in North -West Europe at least, another good weapon for clearing a room was the British Sten gun. It was so cheaply made that the mere throwing of one into a room would generally cause it to discharge it's entire magazine until empty, in the meantime it would be leaping and jumping all over the place. He has seen Germans leap out of windows and hide up chimneys to avoid this !
The entrenching tool sharpened along three edges was the preferred weapon of British Army night raiding patrols along the Western Front in the Great War. My Grandfather served in the Rifle Brigade from 1914 and told me that he had taken a German's head off with a hard back handed cut. He then went on to tell me that the spade then got caught in the German's pickelhaube chain chin strap whilst the head spewed blood all over his boots, and that whilst trying to free it he copped a rifle butt in the mouth from another German ! Another weapon he liked was a very heavy brass knuckle-duster which had a four inch blade folded within it on one side and a four inch steel spike on the other. He used to keep it on his desk and I always wanted it, but, along with his cap badge and belt, he had it put in his coffin when he died.
Listen, amigo, if your grandfather managed to kill even 20 Allied troops with a bamboo spear in the Battle of Whatever, then the buggers must have been either asleep or drunk !