I think the author misses what the purpose of deadlines is. They are contracts between organizations for when software will be available, which are used for other organizations to make informed decisions without needing very tight and constant communication. They're analogous to SLAs in service-oriented designs. In a moderately large (say, 500+ employee) organization, deadlines are essential to get anything done. Sup…
I think the point is that if you do make those commitments you are just making things up, in reality those commitments are worth pretty much exactly as much as not making the commitments.
Where with reality I mean the actual physical reality. I realise that social reality can be different, and even a commitment that you make despite everyone knowing that you don't actually have any basis for making that commitment (no track record, no reasoning, no nothing...) can be valuable.