I'm 1h, but I keep a 2h alt char.  When using my Longsword, I tried the half-sword mode.  I think it's very interesting, though something that doesn't make sense (unless I read it wrong) was that in the game, it said when I used my Longsword as a polearm, the length increased but the speed decreased......shouldn't it be the other way around?  
You don't need to own a sword to know shorter=faster.  Anyone play golf?  You know the difference between your driver and your sand wedge in terms of radial velocity.  And you know when you choke up/down on the shaft, you swing the club faster/slower.