Years go by and we see more and more "ergonomic" keyboards - basically each "perfect for human hands" and each different from the last one...
There is a reason why a typical keyboard looks how it looks. Most of these bent designs are simply trying to be different than the canonical one - I'd be amazed if someone actually makes a proper test of how they affect the user.
Also, think about other consequences: having to learn a new layout (touch typing, muscle memory) and a possibility, that it will affect your abilities to use a "normal" one.
As for the ergonomics - I think there is a good analogy with tools.
Let's look at axes (just because I like axes ^^).
We have all these weird designs that are meant to be "ergonomic", modern, effective or whatever. Every lumberman or orthopedist will tell you this is all bulls.it and that the best handle is a simple stick.
So as a result, this is what we get in survival / military-style products:
And this is how an actual professional axe looks ("professional" as in: meant to be used in high stress, for long periods of time):