Earlier quoted context omitted.
It’s physically impossible for the human brain to multitask like this (multiple streams that both require cognitive attention), and studies have shown that people who try to do this actually end up with long term damage to their ability to focus. It’s very likely that you never were able to do this, and at some point just hit a threshold of damage to your focus that you finally realized it. Also, the same study showe…
I often tell people that, too. Because they usually claim to be multitasking to be more efficient. But is this actually multitasking? When I did data entry, I could "read" forms and type them in while I listened to books on tape because I wasn't actually thinking about the data in the forms. How much cognitive load do the games take? Or the movies? Further, if this is a pleasant experience, who gives a damn whether o…
Then that’s not a cognitive task, or at least one that requires the full brain. I would venture a guess that you might have been able to complete that task faster if you weren’t also listening to the books, or your error rate might have gone down. Or maybe you didn’t fully comprehend the books. Or maybe the material wasn’t too involved and missing some passages here and there didn’t make a difference.
> who gives a damn whether or not it's multitasking or real multitasking or optimal behavior?
Because attempting to multitask causes long term damage. One could say the same thing about drinking or drugs, and it’s clear that short term enjoyment can have negative long term effects.