The two primary methods for transferring heat is convection and conduction. Convection cooling is accomplished by a flow of fluid (air, water) across the heated object. Conduction cooling is accomplished by a cooler object touching the hotter object (heat sink on a computer motherboard, the baffled looking aluminum on a lawn mower engine).
The briar itself is a heat sink, you're transferring heat from the tobacco to the briar. In general, that seems to be fairly effective. Not sure how much more is needed.