Teck is basically controlled by one guy.(Keevil). I doubt the present share price will be much of a factor in negotiations.
You are absolutely right about that. He is a guy that understands future value and will pay for it regardless of the optics. People worry about shareholders of Teck complaining but who controls this company? One family and ultimately one individual. In the past Teck has overpaid for assets ( which other analysts believed were too high at the time - eg Fording Coal ) but it has worked out well for Teck in the end.
In this business, if you always play it too conservative you will never expand your business with quality assets. Quality assets command a premium and some calculated risk taking. That is how Teck has become the giant it is today. Dr. Keevil is a person that understands this imo.