TMFMurph writes,
<<Man, I learned that about 6 months into my engineering career. If working twice as hard isn’t going to double my income, I’m going to adjust the level of effort accordingly.>>
Well, I learned a different lesson from my Dad…and from life:
“No matter what you are doing, Son, do the very best you can…whether it is digging a ditch or anything else. Better work will be rewarded in the long term.”
I practiced Dad’s approach for decades, and while the rewards were sometimes delayed, they always came in one form or another.
Your mileage may vary…and from the attitude expressed above, tend to make for a self-fulfilling prophecy. 
I don’t know. I job-hopped my way through four Fortune 500 companies in the 1980’s and early 90’s, and retired at age 38.
“Makin’ sure “the man” don’t screw you” seems to be a reasonable career strategy.
As business owner, I doubt you’d sign a contract to do twice as much work for a 10% increase in revenue. The savvy employee has the same mindset – it’s just arithmetic.
intercst