PrintVerifier is a runtime verification engine for monitoring interaction between 3rd party components and the print subsystem. Huh? Plain English please?
The answer to all of the above questions and more is PrintVerifier!
PrintVerifier is implemented as an Application Verifier provider. It consists of two verification layers, the PrintAPI layer and the PrintDriver layer. As you might have guessed, the PrintAPI layer monitors the boundary between applications and the print subsystem while the PrintDriver layer monitors the boundary between the core printer driver and 3rd party plug-ins.
Enabling PrintVerifier for your applications and the print subsystem gives you all of the verification capabilities listed above for free. You can find details on how to enable PrintVerifier or any other test that is part of Application Verifier here.