Why is a 9-5 five working days work schedule better than 8-5 five and
a half working day schedule from a long term productivity,
washout/burnout, quality of work point of view.  How does less mean
more on the bottom line?

Would like to back this up with references of studies in this field
supporting the reduction of working hours to 9-8 or even less and five
working days with a full two day weekend.

I would like to also know what are the prerequisites to that being
successful in terms that it will not likely be of benefit either way
if work at the company is not project/result oriented for example. 
Other elements that impact the success and failure would help.

I would also prefer a conclusion section of the results at the end. 
Please don't be too safe and unbiased, if something is outstandingly
right, then so be it and please do stand behind it if you feel it
deserves that support as your opinion backed with the referenced
material mentioned before.

Thank you.

/Dusty

Hello Dusty,

Just a comment - you may want to also consider four day work weeks.
The example that comes to mind is "Four Day Tire Store" that I used to
shop at in Southern California which sells tires on Thursday, Friday,
Saturday, and Sunday (only) and explains in newspaper ads that it
saves money to operate that way.

Odd a quick search of both
  4 day tire store
  four day tire store
does not bring up a home page for that chain. A few (recent)
references in Yellow Page type listings, but nothing direct.

  --Maniac

And I highly recommend this book and this site--they address this
issue quite well, particularly the book:

http://www.simpleliving.net/timeday/

Good luck!

Sincerely,
Boquinha-ga