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This is the bit that worries me..
"The assumption being that they are only going to do it when they feel 100% comfortable that they and their team are up to date on every project and that their absence will not in any way damage the business - or, for that matter, their careers!"
..because if that was me, I'd never be able to take any time off at all, as those criteria would never be met. So whereas at first sight it looks like an incredibly liberating suggestion, it actually could just be a way of chaining people to their desk through guilt.