Currently the user has to know something has been updated on BCL, to decide to update it, or stumble across it when searching for something else. A number of times I had updated measures but users didn't know there was a newer one with new features and or bug fixes. It would be great for a way in the GUI to update all BCL content for the latest version that works on my OS version.
From what I learned in writing measures to download components, I think this could be prototyped in a measure. So yes, while it is odd, a measure can be written that's sole job is to download measures. Another use of this would be to get measure collections like AEDG.