It's almost counterintuitive. First--the advice given by kcvet is right on target. After all, it's common sense to dedicate a pipe to a particular tobacco, and it stands to reason that you should build the cake with the tobacco you intend to smoke. That said, and I admit that this is highly subjective testimonial, I too have found tha cake seems to build faster with burley. And here's why it's counterintuitive: cake is carbon resulting from the sugars in the tobacco that have burned and adhered to the bowl. Here's where it gets interesting. Virginia has a higher sugar content than burley, so you would expect it to form more (does more equal better?) cake than burley, yet many of us are of the opinion that burley forms the better cake. Go figure. And Latakia has an even higher sugar content, so we would expect English/Balkan tobaccos to form an even better cake. And aromatics, many of which have a higher sugar content than the foregoing should be expected to form a very good cake indeed. I am aware of the belief held by many that these tobaccos, precisely because of their higher sugar content, form a softer cake that doesn't adhere as well to the bowl, but it isn't a belief that I hold, nor do I know of any scientific evidence to show whether one method is superior to another. Further, I'm one of those who likes to line the inside of the bowl with a thin smear of honey prior to breaking in. I know that there are detractors who maintain that this method also leads to a softer cake that doesn't adhere well, but the method is recommended by Neill Archer Roan, among others, and my subjective observations don't seem to indicate a problem when honey is used. Again, in the absence of hard, scientific data, all we are left with is the anecdotal information which I and others are all too willing to provide. After all, as I said earlier, cake is carbon (mostly), and when a sugar is oxidized, carbon is what you're left with. And here's the point: in the final analysis, the carbon doesn't care what the original reducing sugar was. Dextrose? Ok, we can burn it and get carbon. Honey, comprised of glucose and fructose--same thing. What we need is a comprehensive analysis of cake, to see what else is present beside carbon, and that missing scientific study of how the different tobaccos form cake. Absent that, we are left with that anecdotal information which many, mysel included, are all too willing to provide.
