Here's the definition used over at cleanmpg:

*Could be dangerous if not done right, possibly illegal*

Forced Autostop: A Honda hybrid will AS (Autostop) in various scenario’s although it is very limiting to a given condition. To high a speed, to cold, not enough SOC (state of Charge), not enough speed since last AS, Defrost or A/C on except for the AH and HCH-II in specific conditions, etc. will not allow AS … Forcing an AS in any vehicle (other then an HSD equipped hybrid), aka FAS, release to IG-II, and engage transmission with a rev match to continue on your way. Pro’s include a very noticeable increase in FE over any short distance trip and is required in a few areas of the US as well as much of Europe, ie. sitting at a stop sign for > 15 seconds or at a stop for > 5 minutes … Con’s include powerless coast, power brake assist is lost after a few uses, power steering is lost although at speed, you do not need it, is illegal in some locales, and possibly both gear reduction starter from excessive ICE starts and pre-mature wear from re-engagements of the transmission at speed.

http://www.cleanmpg.com/forums/gloss...lossary&term=1