What might convince me that Modafinil is a bad thing would be if a lot of people actively disliked the time they spent working. I personally assume most people roughly like or are neutral towards their jobs and mainly want to work shorter hours because it gives them more time for things outside of work, but I'm almost certainly generalizing from the example of me. If Yvain had made this argument I would understand more about where he was coming from and why.
In some professions saying that you "love you work" is a signal of a good employee. So I would expect some dishonesty in self-reporting.
How could we ask the question to reduce this signalling? I imagine only silly questions like this:
Imagine that for some external reasons your workplace must be closed for two weeks. During those two weeks you will receive your normal salary, and those two weeks will not be taken from your holidays. How does this message make you feel?
a) awesome!
b) mildly happy
c) neutral
d) mildly sad
e) depressed
On the second thoug...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.