Comp cams degreeing issue

he said dot to dot it went in at 102* and he had to retard it to get 106*.
yeah this is what had me confused,dot to dot it went in at 102,so i moved the crank keyway sprocket to where it says 4 retard,re deegreeed it in and its now perfect at 106,i now understand that the 4 degree advance is the difference between lobe sep and intake centreline