CA: Almost correct I think. The FMGS will limit the speed to Vmax, but the AT will agressively chase the cca 30kt faster target and will eventually overshoot. Never had the chance to test the feature properly myself, on the several occurences so far as a crew we were fast enough with the corrective actions (touch wood).
In a similar fashion should a flap/slat overspeed be imminent after takeoff / GA, selecting flaps/slats lever up one step will remove the barber pole from the speedtape at once, however the overspeed may still occur while devices are in transit. FDM/FOQA will have a record of the exceedance so PIC better make sure the techlog entry is there as it should.
Last edited by FlightDetent; 9th December 2015 at 19:45.
Reason: Improved clarity, hopefully. :)