As I mentioned elsewhere, warping in ArM5 feels to my troupe a little too much like Chaos of Warhammer Fantasy Roleplay: an insidious force constantly out there to corrupt you whenever you accept some powerful magic (instant transportation, healing etc.) or slightly push yourself (e.g. performing fatiguing spontaneous magic). What feels really bad to players is that it's irreversible, so that whenever a character incurs it, that character is very measurably, forever worse off than before (unlike what happens with wounds, reputation losses, property losses etc.)
This is not so much of a problem for side characters like grogs. First, individually they tend to appear less often in stories, and thus are subjected to less warping (which occurs mainly in stories, in my experience). Second, well, they're expendable anyways ... though I feel strangely bad about saying it!
So, I am thinking about introducing a simple house rule: whenever you would accrue a Warping point, you can spend a Confidence point to negate it. I am tempted to exclude from this "long-term" warping, but I like my house rules as simple as I can make them. Any serious drawback? Remember, seeing magic used a bit more freely during stories would be for us a feature, not a bug.