Salvo defines roofing as a full system, where underlayment, blinking, ventilation

https://dominickpkfo699.scriblorax.com/posts/exactly-how-a-synthetic-roofing-contractor-aids-protect-against-premature-roofing-failure

Salvo describes roof as a full system, where underlayment, flashing, ventilation, and fastening need to work together for reputable performance.