This is a very good read. The only issue I really take with it the notion of the estimates constantly being correct, while later adding all of the other organizational factors that can create a change of course.

IMO that means that the estimates he's talking about being accurate are fairly short term.

Totally agree with him on a lot, especially only the developer working the task can truly estimate it. When you're talking about time measures, that's the only hope of them being accurate.

When I talked about story points reflecting complexity and not time, it was specifically because time is variable by person. If the team isn't creating a time estimate on a task, that's much less of an issue.