Man, I gotta push back on this one. A bad wall type in your template is not the same thing as a clash. What you chased for 3 hours was a modeling error, not a real coordination issue between trades. Actual clashes are when the duct runs straight through a beam or the sprinkler main sits inside a cable tray, stuff that needs two different people to sit down and figure out who moves. Your template problem is a you problem that would've shown up on every single project using that template, so the fix is way bigger than one wall. Check your template file, purge that wall type, and you just saved yourself the same headache on the next ten jobs.