Tell that German and Danish GS
Seriously, polearms balance is so fucked up in this mod that damage output of some of the best two handed swords is considered weak among their two handed polearm brothers.
1 less cut damage (German) or 1 more cut (Danish), but you get +4 pierce (German) and +2 Pierce (Danish) and a +2 to speed (both).
I agree that it's definitely not a "weak" cut dmg, they all have good swing damage. And +/-1 cut damage isn't really that big.
The thing with the Glaive is that it has a very good speed relative to length, same with many polearms/2handers, while still doing good damage.
And regarding damage output. I'd say the +2 speed gives the Danish/German a higher damage output than the Glaive.