Yes, we also have conclusive evidence that centerfire cans can cause these same issues when dirty. Travis Stevens @ TS Customs as well as other TS Customs PRS team shooters have seen the effects. It isn't something that will ever be seen for most shooters though. We've only discovered it when working with extremely precise barrels with very finely tuned loads. Thus far, a dirty centerfire can isn't going to stop you from shooting 1/2 moa, from what we've seen. Yet it can stop you from shooting better than that.
To clean a sealed can, you dip them in horrible solutions that dissolve the fouling. It basically creates toxic waste though... which is not good.