You're absolutely right about the floor space, I had not considered 3x4m glass boxes, and I apologise that my post came across that way (pure provocation) -- perhaps I was in a sour mood. I have not worked for a significantly wealthy company in my history, and so it has never been the case that a private office has been the most cost-effective way to improve profits. To make a reasonable argument: Typically the equation is simply money-in vs money-out. If you can spend an extra 100k a year on private offices for developers and get 300k a year in chargeable services/development effort, vs spending 100k on another salesman and get an extra $1m in net profit, which would you choose? The choice here is clear and 2 monitors vs 1 monitor is a $100 cost for 1.5x efficiency, and is an absolute no-brainer. An office on the other hand is usually not the most cost-effective option, but if you have enough cash to fund all of the other more cost-effective strategies plus private offices, then it is another place in which management can increase profits.

Please follow up with your thoughts, and again, I apologise if what I wrote was inflammatory or came across that way. It was likely coming from a position of "unknown unknowns".