What ?! Working are you crazy ? That's super unproductive ! I've heard that at Fluber they were also trying the 3 hour work week which is of course much better than the 40 hours working week. \s
How much actually useful work did you get done this week? If you didn't have to put on a performance of being at your desk for 40 hours, but were able to do 3 hours of really high-quality work, would you end up more or less productive?
In any case, yes, absolutely less productive. The time you need to communicate with other people in your team probably already amounts to at least 3 hours in your week.
Not counting the time you need to build back your mental context of the task you are working on. Why you were stuck last time ...etc.
I understand the feeling that people have that there should be a more relaxed schedule and restrictions on the location you are working from but in the end I'm unconvinced that it improves productivity. No saying that you should work 80 hour weeks and be be stressed out of your mind but the reverse is not true either.