I'm not...I only just started, but I'd rather have separated mine than have to worry about them.
But I remember, once i picked up one of my dwarves and as I put it back in the cage the other jumped on its back and attacked it..
(I'd only put it back in the cage for two seconds, I'd just figured out it was a boy and my other was a girl, so I was setting up their spare cage..)
but two seconds later they were happily together again :s...Like it's hard to gauge how well they actually get on.. and the ultimate decision is up to you.. But they will be ok if you decide to separate..
Chances are that it's probably from a scuffle.. but I know other dwarf hamster owners have put their hamsters in completely bare cages to stop them having anything to fight over, and are taking it really slow in introducing new things.. but it's a lot of work, the animals don't have anything to keep them occupied, and it takes a long time - with no guarantees of success..
If you wanted to look into that possibility I'm sure Hope would give you some advice..she has a thread on her two robos, barnaby and troy..
Sorry I can't help..I'm sure somebody with better advice will be along soon
