Wasted "cognitive capacity" can be easily twisted into just another excuse for the Man to squeeze every last ounce of work... I mean life, out of a Human Being in the name of enhancing shareholder value.

Of course, too much of anything isn't a good idea whether it's TV, reading, gaming, or sex... Maybe not sex. Anyway, what I'm getting at is playtime should be whatever you want it to be from knitting, to sitcom viewing so that you can rest and cognate better later. I think that a truly important catalyst for innovation is actually variety, and not what is subjectively being "wasted" while we rest.