Comment by JohnFen
For me, the difference is that work is something you have to do no matter what. Play is something you can do purely for enjoyment and don't have to keep doing when it's not fun.
I don't think that you can work and play at the same time. They're two entirely different things. You can, of course, have a lot of fun doing work -- but it's still work, not play.
You can work and play, if the playing is your work.
But you're right. You can't do it same time. If concentration is needed, one can't do other things except to concentrate. Otherwise, no concentration.
In my experience, alternating playing while working helps a lot to refocus. It's the same when learning things. one just have a timespan of round about 12 minutes of full concentration. after that a short break doing completely other stuff help to refresh the concentration tank.
But, keep in mind, the work progress and understanding of things need to be reread and reunderstood, having a break once. That was my problem. Every 20 minutes a cig and a break for 5 mins. While break talking about the problems fosters creativity. But then, 5 mins are needed to get back into topic. So actually, this was bad :)
So I stopped smoking in an experiment. Guess what. I've finished all the work in 2 days without breaking, while being on it for weeks.
My boss didn't want to pay me more, so I quit quitting smoking. Haha.