I click the share link below the video on youtube and copy that link
Then paste it into my post and it looks like this:
http://youtu.be/MFCNVvvmxNw
Then you need to delete everything left of and including the hash mark like this:
MFCNVvvmxNw
Then I highlight that portion and click on the green video icon in the menu and that wraps the tags around it.
PS - Greg, you're a good sport.