Seams from islands is only used as a lead-up to selecting the mark as sharp feature... You could always select the entire mesh and clear seams once the edges are marked as sharp :P
This is kind of basic stuff so I think most people probably know about it already. Otherwise I thought it was pretty good, could maybe have been a bit shorter though. However I did find one case of misinformation in your video. You mark all of the seams as sharp when it really should just be the other way around (all hard…
Well I've used Blender since 2010 and have always had trouble with efficiently exporting the low-poly model with the right normals/smoothing groups. As far as the Blender Wiki is concerned, it doesn't explain this procedure there. So fair enough if people "should" know it - I didn't :P As far as the technique is concerned…