Many information systems can be implemented in a week. You could set up email, an e-commerce site, a CRM, SCM, or even substantial portions, if not an entire ERP system depending on the size of the company.
A week is a long time if you know what you are doing.
By not letting someone acclimate to your tech environment, your potentially shoving them off on the wrong foot (not to mention stressing them the fuck out,,,which WILL kill their productivity). A mistake that could cost you months of 50% productivity because you didn't (as a company) empower your developers to do their best work.
When I see managers pulling some "whip them harder" management styles, I can't help but be left with the want to remind them about the french revolution. Pointy-haired bosses will soon figure these things when "their" work force becomes a bit too empowered.