It is yet known that Android Developer Verification will not apply to apps installed via ADB as written in this support page:
Any app installed via Android Debug Bridge (ADB) will not require verification. This will ensure developers can easily build and test apps that are not intended or not yet ready to distribute to the wider consumer population.
This means keys are checked on installation but not on every run, since above exception exists.
Honestly, with that in mind, there is really no added benefits in terms of security for rolling out 
Developer Verification - it only profits Google by supplying ID documents of developers to them, and provides no benefits for end-consumers whatsoever 