A dry moment is an unhappy one for Dief, but strangely, once the leaves are gone, the stems can wait for a long time for moisture to return. Clinically interesting but since we're in it for the gorgeous leaves, try to keep as moist as possible w/o risking rotting the roots. I'm sure you'll get along well with it if you can keep a peace lily looking good.
I like your strategy of splitting it up to double your odds. Cramped, tangled roots can be a problem for some plants. Dief roots are BIG and need room to roam.