I agree that in many cases not having a permanent office may bring cost savings but the question I would ask is why are so many people still having to get on trains to go to meetings because, to quote my members "you get so much more done face to face".
In addition while being freed from time constaints might be great in some ways, the cry I hear from many is that the work never stops they find it great when they finally have an office so they can just go home
Finally many of the start ups who I work with feel very isolated and have found working in a Hub to be very motivational.
So all in all, without walls yes, without an office I think the jury is still out.
But really being ahead of the curve means exploiting advances in technology and cloud servers, like Google Docs, Dropbox and email-killing chat app Slack, to abandon the office altogether. Why? To benefit from the increased cost and time efficiencies that come from ditching unnecessary rents, superfluous emails, time-wasting internal meetings and travel. Meanwhile, you can experience the creative freedoms that come from not being constrained by the clock.