> the only reason that anyone is giving you a paycheck is because they are getting value in excess of the amount they're paying you
If by value you mean political value, yes. If by value you mean return to the company for the compensation, that has nothing to do with anything. If there is one thing I have learned in my storied career is that making your boss happy enough to defend your being there is all that matters. I have seen so much deadweight in a company keep their job merely because they were willing to tell their boss what they wanted to hear.
> Whatever amount of job security you can wrangle comes only when you consistently appear to be providing value in excess of your compensation
It took several years to convince my wife that my job security comes from being able to land a new job, not keeping it. I'm always working with new libraries and technologies, staying in-front of (or at least abreast of) what's currently hot. Recruiters are always trying to poach me. Amazingly enough, I landed in a job where I both get to keep my education going and implementing newer technology and my boss likes me. I am coming up on five years, but I know that could change at any moment if pressure were to come down from above.
> What you say about HR is spot on as well. It seems obvious to me, but I'm frequently surprised that it's not obvious to everybody.
Because it's not against the law for companies to lie to employees but it is against the law for you to lie to your companies. I've been in big companies and small companies. They all tell you H.R. is there to help you, to make things better, to work out issues. If you're someone the company wants, H.R. may even work on your behalf (after the manager approves). It really nails you sideways when you've had it good for years to then have the company suddenly turn on you. When you are made to feel as though you are unjustified for breathing in the company's air. It's a huge shock.