You know, I didn't really believe it until I tried it, and I'm not certain of why it works.  As near as I can tell, anything that reduces friction between your shin and your boot helps.  I think shin bang is the result of the tongue of your boot pulling your shin down, while your body is pulling your legs up.  The shaving is essential for the low cut socks though.
As for know I wear smart wool socks, non-shaved legs, and properly fit boots, haven't had shin bang in three seasons.  You could also just stick to landing switch all the time.