"Enjoy" isn't necessarily the relevant metric from which to predict productivity. I enjoy drawing my webcomic, and it only takes me a couple hours to do each one, but I haven't the patience to do more than one page a week - not because I don't enjoy it, but because my brain resists too much of the same thing spaced together too closely. Conversely, I don't think I could be said to "enjoy" some of the pointless Flash games that have eaten entire days of my life singlehandedly, but I went on playing them anyway.
"Enjoy" isn't necessarily the relevant metric from which to predict productivity.
And this superficially unintuitive observation has been studied right down to the level of neurotransmitters in the brain. Crudely speaking it is the difference between the opiod dopaminergic systems. (Flash games and amphetamines both come down in the 'dopamine' category.)
ETA: There is now a third thread, so send new comments there.
Since the first thread has exceeded 500 comments, it seems time for a new one, with Eliezer's just-posted Chapter 33 & 34 to kick things off.
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