I find that different dews take separation differently to, binata, adelae and indica for example I can practically pull up and tear roots in the process of repotting and they don't care, hell new plants normally grow from the left over roots (excluding indica), pygmy drosera on the other hand go into shock and die if I am not pedantic, petiolaris generally go into shock for a couple months, but dilato-petiolaris doesn't seem to mind much.
And most rossete seem fine with rough care (spathulata, venusta........)