There are different preferences and traditional ways to make hand cut dovetails and then there is a way that adds one extra step but removes all need for the conventional use of marking or cutting gauges; methods normally associated with laying out both through and half-lap dovetails.
When I first saw the video played back to me, it took me 30 minutes in the presentation to cover the essential and core issues, but when I’m at the bench, working on my own, a four-inch span of say three equally sized dovetails takes me 10-15 minutes per joint corner. I think if you give it a try you may want to use it forever. Whenever you see any of my half-lap dovetails in my work, the chances are I have used this method. If you are one of those that likes the gauge lines across your dovetails to show that they were hand made and not routed, you can run a marking gauge across the shoulder lines after you’ve done.
I might add that in the presentation I do use a router plane but if you don’t have one you can just use a widish chisel for the same work.
Here is the video: