As someone with a degree in fight coordinating, I can say that a hand held controller is unable to emulate the mechanics of sword fighting. There are two main reasons:
1. When fencing, when your strike is parried, your arm is either moved or stopped. With a controller your arm swings freely through. How and where your arm is halted determines what your next move would be.
2. The lack of weapon weight removes the inertia of your weapon. A bastard sword moves the same as a foil. This can be accounted for with ingame inertia, but inevitably the game will end up lagging behind the player in their movements, as you can't feel the weapons response. The player will probably just become frustrated with the sluggish feel of the response time.
That said, congrats on these guys for making a cool half mill.
I was wary about this game for these same reasons, but after watching their technical videos (read: not the silly mass-market one) I've gotta say they've done their homework. Their solution is in the videos and commentary on
this page, with the short version that Clang is supposed to be something of a "thinking man's" swordfighting game, and if you fail to anticipate your opponents moves and get out of position you're already dead anyway. People who are playing the game skillfully will not be over-committing and will instead be ready to flow from movement to movement in accordance with their avatar.
When we come at this from an engineering mindset, it’s natural to get hung up on the fully general problem of what happens when a big swing slams into a strong block. And that is a difficult problem to solve, when you put it that way. But people who play CLANG are going to be inhabiting the characters of trained swordfighters, who don’t fight that way--instead they are thinking a couple of moves ahead, adapting to what the adversary is doing, getting ready to flow around it into the next move.
So the gameplay will be less about beating down your opponents guard and more about executing your techniques faster and more accurately than your opponent. They don't talk much about how to handle inertia and the "feel" of different swords, but they're only launching with the one sword anyway, so it's presumably in the "worry about this when we have more talent/resources" bin.
What I'm waiting to see is whether their motion controller lives up to the hype, and whether it turns out to be an enjoyable experience- I'm too cheap to shell out $100+game for a duelling game few are playing. Hopefully somebody in this thread already donated for a copy of the game and can give ground zero feedback when they release