I've watched the video once and although he seems to end up with nice joints I can't help thinking he brushes over several important points - specifically that you need to bevel the ends of the boards (in their thickness) and that therefore the cuts down the length of the pins need to go further on the inside than the outside.
The classic diagram to draw out the bevels is there in Joyce but the text is a bit terse.
In my opinion, the best description on how to cut almost any sort of joint is Charles Hadfield's "Woodwork Joints" book in the series of Woodworker handbooks. He gives you six pages on bevelled dovetails, including practical points such as how to economically cut your stock and how to modify a shooting board to plane the ends accurately.
It's still a fairly easy book to find second-hand though some vendors have noticed the good comments it has had from US woodwork writers such as Chris Schwarz and adjusted their prices accordingly.
That said, cutting bevelled dovetails for real is something I've still not got round to, so I'd be interested in following anyone's real life experience of trying.