Respect confidentiality, however I have witnessed and seen many water fountain conversations regarding potential employee names being tossed around.
"Hey you worked at this place, do you know this guy/gal?"
"Are they any good? Look what is qualified on this resume, is all of this true?"
"I have heard too many bad things from people with the same roles but nothing but praise from management".
Last but not least, Project Managers, Engineers, Technicians and even Sub-Contractors can talk a big game on paper. My rule is this, come meet me on the white board for some brain storming, problem solving and brief technical writing, we will see what you know. I dislike promising resumes, linkedin rhetoric and long winded stories about how someone is so good they are asking for top dollars. Prove the basics on the white board and we go to the next round, if we find holes in your game...GOOD BYE.
Listening to old friends vouching for one another is not a good way to hire people you anticipate for critical positions.