There's no bulk witness-line edit, so for existing strings you're stuck editing them one by one — but if you're re-doing them anyway, redrawing is faster than it sounds.
We actually built a plugin for exactly this: One Click Line Dimensions places a whole chain from a single line drawn across the elements, with the reference rule set once in settings instead of per pick. Re-dimensioning a wall becomes a couple of seconds.
I'm the developer — you can try it for free at archplug.com.
