http://www.bbq-brethren.com/forum/sh...ad.php?t=47586
Pretty decent article I found about smoke rings. There's plenty more on this site if you're keen on looking.
As far as the non rendered fat coming out a lot of people (myself included) tend to cut out some of the fat that's between the point and flat as well. I like to do this so I can make beef tallow from it rather than have it end up in my trash can.