I have never used the thing, but stabby 1H swords are undervalued by a lot of players. In the current battle/siege metagame almost everyone has decent (45+) armor, and 1H stabs are quick and easy to pull off even in tight spaces. I think the crusader sword could use a buff of 1 speed, but I think the main reason it isn't used much is that many players have access to +3 heirloomed weapons that outclass a +0 crusader sword in everything. The +3 version doesn't offer anything special compared to other +3 stabby swords. It isn't worth burning 3 LP to make one when there are other options that cost way less (or are even free through clan armory).
The stabby 1h swords have a high ceiling (you can do insane damage on a held head strike with high speed bonus), but a lower floor (well-timed sideswings still glance and get you killed, and when your stabs are blocked you are stunned and left open to be hit). I think many folks are content to be consistent with an Elite Scimitar or something, even if they don't have the capability to 1-shot anyone.
Crusader Sword is pretty balanced with Side Sword now (trades 1p and 2cm for 1c), but has a late Medieval look instead of Renaissance. Renaissance gear doesn't fit well with most armors (only Black Armor and some of the cloth stuff).
To the poster above that wants a "cut Espada", you could say the Liuyedao and Niuweidao kind of fill that niche, although they are Eastern and 3d. I see what you mean though, a European sword in that class would be nice.
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