You can’t measure it easily. Velocity’s VALUE comes from its INHERENT consistency. A fixed iteration length helps drive the reliable rhythm of a project. Without this rhythm, you are constantly revising, re-estimating, and reconciling, and the ability to predict out in the FUTURE is minimized due to inconsistent results.

If, on the other hand, almost everyone is going to be out a week for the holidays or a couple days for company-wide meetings then by all means adapt iteration dates or velocity accordingly. LIKE most agile practices, these are GUIDELINES, not strict rules.

You can’t measure it easily. Velocity’s value comes from its inherent consistency. A fixed iteration length helps drive the reliable rhythm of a project. Without this rhythm, you are constantly revising, re-estimating, and reconciling, and the ability to predict out in the future is minimized due to inconsistent results.

If, on the other hand, almost everyone is going to be out a week for the holidays or a couple days for company-wide meetings then by all means adapt iteration dates or velocity accordingly. Like most agile practices, these are guidelines, not strict rules.