> For binary packages of any sort the mtime would always be different, same for > stuff from the kde store since that'd rm the old tree first (I am guessing).
Different but not necessarily newer. I still recall the trouble we had when we did major theme changes in Plasma 4.10. When you install your machine with Plasma x and then update to Plasma y which was released before your install, the mtime in the package will be lower than the one of your local Plasma install causing havoc to your theme. At least that was my impression, so it's not as straightforward or reliable as you just described unfortunately.
