Like we said before things changed for 6+ firmware, also i'm missing 4 minutes in the vid, jumps from 12.43 to 12.47 with a vid break, who knows what is being done in between.
Beside that i won't work if you unlock and don't change SIM's which was also mentioned.
From:
http://support.apple.com/kb/HT5014
iPhone: About unlocking
Summary
Only some carriers offer the ability to unlock iPhone for use on any carrier. Follow the instructions in this article to unlock your iPhone.
Products Affected
iPhone
To unlock your iPhone, check with your carrier to ensure that they offer unlocking and that you meet the requirements to obtain an unlock. If both those requirements are met, ask your carrier to unlock your iPhone, then follow these instructions:
Ensure that you've waited the recommended wait period provided by your carrier.
Back up your iPhone.
Erase the contents of your iPhone.
Swap the old SIM card with the one for the new carrier.
Complete the setup assistant and restore your backup.
Additional Information
Follow the steps below if you experience issues or receive the following error message displayed in iTunes or on your device:
"The SIM card inserted in this iPhone does not appear to be supported. Only compatible SIM cards from a supported carrier may be used to activate iPhone. Please insert the SIM card that came with your iPhone or visit a supported carrier store."
Restore your iPhone.
Contact your carrier to verify that the unlock was applied in your carrier's system."
Both bold items erase the activation record, which is what is necessary to activate the unlock.
So no he has not proven me/us wrong (yet)
he might though