I'm looking at some instruction videos on stropping the razor but I little unclear on how the razor sits on the strop. Looking at the videos at first glace it seems they have the razor at a slight angle where only the edge is touching the strop. However if a look a little closer it seems they have the edge and the spine in contact with the strop at the same time, is this right? Also should the strop and the spine be in contact when ascending and descending? Please help if you can, thanks.