The theme of Swords so far seems to be around evasion, shadowstepping, dazing/stunng (look at the stealth skill), and just generally being difficult to kill, so that doesn't sound right. Plus, D/D is already... basically... an aoe whirlwind move. Perhaps some kind of "cross cut" move. In fact, that sounds like a good name for a skill.
Interesting thought: Ranger and Warrior support weapon skills are entirely from Warhorn. I wonder if that could be worked into the Thief motif somehow.
---------- Post added 2012-06-11 at 06:35 PM ----------
In addition, and I've brought this up before, Thief has the least weapon options, except for Elementalist. (yes, we have less than Engineer, because of their kits. I did the math once on how many different
unique weapon combinations Engineers have with the different ways to combine their normal weapon slot with their utility slot kits, and the number was over 200)
Just look at the chart here:
http://wiki.guildwars2.com/wiki/Weapon
Without counting our underwater weapons (which are always the same setup anyways, unless you grab two Harpoons or Spearguns for some reason), we only have 7 weapon combinations total.
Elementalist, not counting Trident... has 5.
How the hell did that happen?