Feature request: runtime ppa dependencies (not build depends) should be able to be installed from other ppas if the ppa maintainer selected the ppa as depending on another ppa

I was bit by this with a runtime-install dependency of a package that was simply there to request from the user the install of a rom on first install of a program that needed it (there are more than one that need it). So it was natural i put in the building of that package in the same ppa as the package that builds the static library emulator that is used on 'build-depends', since it is used by more than one project.

The idea is that the rom would only be uninstalled after all the packages depending on it were uninstalled. Unfortunately launchpad ppa transitive dependency when you 'depend' on another ppa only applies to 'build-depends', not to runtime libraries that the user needs to install. I have no idea why this is so, since it doesn't give any more security. I'm asking that when a admin of the launchpad ppa makes it depend on another ppa, that both are used to install software, not just building.