I'd hate to hold anyone responsible for their memory - AFAIK no one can remember what they don't remember (this is why we take notes and run script) - I can only assume their memory is complete. With other areas a guess/"instinct" may be good enough - with security I prefer proof. Even if they didn't specifically install open-vm-tools it could well have been a dependency
Great point. It made me laugh. :-) Hopefully I will embrace part of that knowledge and way of life with time.