If I understand this bug correctly (and my experience corroborates this) it's not a timing issue between shutdown and startup - it's a timing issue between various parts of the startup process, so waiting with the machine powered down should not have any effect on the bug.
Sébastien:
If I understand this bug correctly (and my experience corroborates this) it's not a timing issue between shutdown and startup - it's a timing issue between various parts of the startup process, so waiting with the machine powered down should not have any effect on the bug.