Cam Timing

I didn't want to highjack the op question on cam timing, but I do have a question about it. When installing a timing chain I always brought up #1 on the compression stroke, turned the cam gear to the 6 o'clock position and the crank gear to the 12 o'clock position, then I installed the distributor with the rotor pointing at the #1 terminal in the distributor cap, I never had any trouble with starting the engine or adjusting the ignition timing. I was always told that putting both gears at 12 o'clock would put the cam a 180* off. I was even told this in tech school. Is the 6 o'clock 12 o'clock method correct? Also, back in those days I didn't degree the cam.