also agree with previous. clacker comes on at .823 (i KNOW that
)
once above vnav-descend profile i (also) strongly recommend NOT to use VNAV to recapture as it will dive heads down for the path. while it is true that there are 'protections' the problem is that the auto-flight system installed works very sloppy. in some situations you can even get into over-speed with LVL CHG set to .82/340 as the auto pilot lacks preciseness.
or in other words: even if your entries on the MCP are 'in limits' the inertia of the system will bust those entries/limits. not sure what your employer makes of this.