“Unintended behaviour” refers to issuing an ACAN where no ACAN was necessary. For example, you know that it's not in the public interest to have a second bid, but you issue an ACAN and your authority goes up. Really, you should have never done that in the first place. You should have called it a sole-source contract and stayed within the limits assigned to you.
On December 1st, 2009. See this statement in context.