True, but if you spin the distributor enough, you can compensate for it and realign the timing marks. WHat i was getting at was that if you can set 10 degrees BTDC, your timing is perfect...no matter where you stab the dist at.
It may not be where it originally was, but as long as your timing is ok you are fine. If you can't set the timing (intake in the way) then you need to restab the distributor.