Can someone in the know explain to me why in the Goode Tech Manual, the depth of fin and length of fin measurement are .030 difference between the slot and dial calipers. This makes no sense to me, although I have only the electronic caliper and not the dial. Also, in their pics they do not use the tips of the caliper to measure length but lay the straight edge in the side of the fin. This makes sense to me but the plastic square housing for the electronic display sticks out not allowing for an accurate measurement. When you close the jaws, the tips are together, reset to zero, so it seems to me that you should measure by using tips.