>Always wait ten seconds between display state changes
Yes, that's a good thumb rule when dealing with hardware+software. Not just for displays either. Seen many cases of it. I have a USB modem for mobile Net, for which I wait for a few seconds after it shows the login dialog, to make sure it has fully initialized, even though the dialog seems to indicate it is ready. If I click Connect in the dialog a few seconds too early, it connects but often then the speed comes down to zero quickly. Disconnecting, closing the dialog, removing the modem, waiting 5 seconds, plugging it back in, waiting for the dialog to come up again, and then waiting an extra 5 or so seconds, fixes the issue.
Remember issues like this from my system engineer days too (Unix and related support to customers in the field). Once a Unix minicomputer was not booting. (Was working for a large Indian Unix hardware vendor then - India got Unix early and became a Unix country, because of an RBI mandate on bank computerization.) This was at a hospital and they had a lot of critical patient and billing data on it. Backups could have been restored after changing the hard disk, but that would mean machine downtime on a live hospital system. Maybe a lot of time to get a replacement hard disk too, from head office.
Others had tried - hardware engineers. I was called in (I was a system engineer, aka software troubleshooter). Tried rebooting. Did not work - hung before kernel boot messages. Rebooted again. No luck. Did it again. Nope. Others said, drop it, lets try something else. I said - wait. Rebooted it again. It came up fine. End of story :)
Of course, I did a lot of other (and some harder) kinds of troubleshooting stuff in that role too, not just rebooting boxes :) But the point is that this kind of experience and common sense often worked when sometimes other things didn't. So it takes all kinds of skills ...