[quote=@Ciaran]
With that ability, though, concepts such as pressure are irrelevant. Therefore, something affecting a wider area, such as a slap, or better still, a body slam, would be more effective. Additionally, the fighter would want to avoid the other problem, of his fist shattering. Therefore, they would want to actually attack more slowly.

In short, you've created someone who fights most effectively by doing the exact opposite of what most people do to achieve te same thing.
[/quote]

I did come up with how he could attack more slowly, but that would only work on sneak or underhanded attacks or they would simply avoid him. I wonder if a scientist could figure out how slow you'd have to be to not injure yourself on a 1 atom distance stop. 

To make the ability slightly less pathetic you could say that if the enemies atoms absorb all the damage then it would also absorb the force hurting the guy with said ability. You would also have to say he can only destroy the single cells that are touched. I forgot how many cells the skin is thick, but it would still likely take hundreds of attacks to break through, more so than the...what...septillions that the atom ability would require? 

Got me thinking for the atom smashing, though, it it would set off any type of nuclear explosion depending on how he destroys their atoms. If the area of skin would provide enough material. Also if the person would feel themselves loosing a single layer of atoms and if that could be major trouble even if it doesn't cause a nuclear reaction.