How to Make Samurai Katana Swords - Part 2

"so what tech did it have? I'm not denying that it has a use and is effective at what it does, but how is it improved over just being a slab of metal? What has evolved in it since their creation?"
Pattern welding and lamination was developed in Europe centuries before they did it in Japan. It was also easier to make good blades in Europe because the iron was of a much purer quality. The iron rich sands of Japan is a very poor resource, and needs to be worked with extensively to make it decent.

"Fact is Longswords were designed for thrusts and were reinforced with weight to keep them sturdy."
No no no no NO! No European sword was "reinforced with weights". If you want a stiff blade, you hollow ground it (and that involves weight REDUCTION). And the first longswords were made for cutting first, thrusting second. It was as metal armours became more commonplace that the sword evolved for thrusts rather than cuts. And they were still not meant to thrust THROUGH plate armour.

Another thing: the hamon absolutely, categorically does NOT "catch cracks"! The hamon simply marks the transition made from differential hardening. And what's more: if a crack is deep enough to cross the hamon, the blade is ruined.

"My assumption is that these techniques were developed because they aren't as sharp as katanas. It's an evolution of technique, not the sword."
Then you'd be wrong. The swords weren't half-sworded because they were less sharp. Rather, they were less sharp *in order* that they could be half-sworded. The techniques evolved because you cannot cut through metal armour with a sword.

"Katanas held their sharp edges longer with the hamon."
The hamon is simply the temper line, and has nothing to do with sharpness. You can easily have a hamon between soft steel and even softer steel, which would still not make for a very sharp blade. Also, European swords were often differentially tempered, too: soft core, hard edge.

Furthermore, no knight anywhere disregarded the bow as something that lacked skill. It lacked honour, sure, because there wasn't the "honourable" confrontation between nobles. However, they did often practice archery for sport, and were very familiar with the skills involved, as we can see from Edward I's policies, that every able-bodied man had to spend a certain amount of time each week for archery practice. Now the CROSSBOW, on the other hand, could indeed be deadly with little skill.

"but it wasn't their forte and to be dismounted was considered very bad."
Not so, being mounted is not always beneficial. In a pitched battle, with little room for manouvering, being mounted is very, very BAD, because cavalry only has advantage from momentum and mobility. From a stationary position, cavalry is extremely vulnerable. And infantry defends better than cavalry, which is why knights were sometimes dismounted, as the English knights were at the battle of Crecy.

"Hardened steel? That kind of metal, though tough and capable of keeping an edge, is fragile."
You are thinking thorough-hardened. But there are varying degrees to hardening, and almost all swords are hardened one way or another.

they really can't be as sharp. After a good initial sharpening, maybe, but not over time. Katanas held their sharp edges longer with the hamon. Also, Europe didn't have proffessional sharpeners like Japan did. That makes a huge difference. regardless, you cannot speak of comparisons using extremes. So we compare the relative sharpness of the avg katana vs LS

Any sword can be used in more than just cutting. what's your point and what does gloves have anything to do with swords?

Yes there were knights on foot, and they trained as such, but it wasn't their forte and to be dismounted was considered very bad. But the point was that they didn't train as readily in multiple arts of war, hence not as dynamic as you claimed. They still worked very well and are probably the best cavalry chargers, but I their honor handicapped themselves. Disregarding the bow as a weapon that lacks skill and honor isn't a very tactical idea.

Hardened steel? That kind of metal, though tough and capable of keeping an edge, is fragile. It is stronger than soft steel but snaps unlike soft steel. katanas use both, hard on the edge to hold the sharp edge, soft on the inner core to be flexible. hence more durable. It is not the best of both worlds to just use hard steel.

There were knights that were in foot..

"No soft metal to absorb damage..."

The Europeans had different tempering technology, it was called harden Steel.
Harden Steel takes the best from both worlds; it absorb damage, and it was also much stronger then soft steel...

Also that was not a Blood Groove; it is the Fuller. "The purpose is to strengthen or lighten the blade, rather than to allow blood to flow from a stabbed person. A well made knife will have a forged fuller to increase the strength in the spine of the blade."

Oh and That is a big Myth, you can not just cut a sword in half...

Yes and no, they are but aren't as sharp as katanas. Why did I say that?

Is because they did not always sharpen the Swords so sharp that you can cut any thing.

Most long swords can be more or less about as sharp as a katana if needed to. They have it just blunt enough to use protective gloves (not just any gloves)... And the fact you can use it more then just a simple slice and dice...