I was all prepared to answer until I watched the video and saw that he never forges any taper into the blade.
I will guess that he is doing this because it is a san mai type of blade (outer layers are damascus and the core is a solid piece of steel) and that this has something to do with getting the core turned up to meet the point of the knife. Sometimes you do funny things with pattern welded blades that are in regards to manipulating the pattern as opposed to being necessary in making the knife. If he forges the back edge down towards the point he will thin the patterned steel out and the core steel should stay more true (full width), then he flips it over and "bends" the core back up towards the tip so that it is exposed for the whole cutting edge. If he simply started out by bending the core/cutting edge up, he would be left with a corner of patterned steel on top that would have to be cut off. It would be easier to visualize if the 2 steels weren't all the same color while forging.
In a normal knife, the forging process requires what we call a "pre-form". When you are forging the profile, you will turn the point down towards the cutting edge a predetermined amount. Then when you start to forge the bevels and taper into the blade, the point naturally turns back up. If you can get your hands on some play dough or modeling clay you can see how this works really easily. You have to always think about where the steel is going to go. If I hit it with a hammer I am displacing material, and it has to go somewhere. So as I thin the the cutting edge of the knife, it naturally has to get longer. If I don't start off with the tip pointed down, the blade will automatically take on a banana shape as the cutting edge gets longer than the spine. So I compensate by bending the blade the wrong direction from the start.
