Interesting.
I was taught to navigate from the airfield on my two PPLs (M then SEP), then for my CPL told to use start points. For my real world VFR nav, I in reality pick a start point not far from the airfield and as near as dammit on a straight line route to first proper waypoint from the airfield if precision nav is really important (microlight cross country competitions for example), but just start at the airfield if it's not.
What brought this to mind was flying for an SEP reval with a lapsed low-hour CPL holder who told me that he was taught to use a start point for his PPL, but to start from the airfield for his CPL.
Looks like the way I learned was in the minority, but the way I actually fly is a pragmatic halfway anyhow.
G