Yep. Anyone claiming to be working more than 40 hrs is implicitly revealing that their job doesn't require much thinking.
It is possible in crunch time to work harder on difficult problems, but not for longer than a few weeks at a time followed by a few weeks of rest. Regardless how you account for the time.
I arrange my work so that it doesn't require much sitting and thinking. Instead I come up with a way that I can write code to visualize what's going on, iteratively test solutions, or read to select from approaches on the Web. I guess you're right, when it comes to something I would have to invent from scratch I panic about having to think for myself.
It is possible in crunch time to work harder on difficult problems, but not for longer than a few weeks at a time followed by a few weeks of rest. Regardless how you account for the time.