Yeah, one man’s "challenging but feasible" becomes the next man’s "arbitrary".

The difference between small increments and giving a status updates every week is that if your task needs multiple status updates, it’s not small increments.

Also small increments mean a piece of work that can measurably be evaluated as done. A status update is not a "done" status.

If someone fails to deliver a small increment, you find out soon, and the team can re-assess, and it doesn’t carry the stigma of missing a deadline.