The members here have found that upper air inlets on the FB, will move heat from the FB to the CC without adding additional air to the fire...
So, the lower air inlets control the heat and the upper air inlets move that heat to help reduce fuel consumption, reduce creosote and even out temps across the cooking surface...
They make your smoker a more versatile cooker...
One member has found he can control his RF smoker at 80F for smoking cheese...
Takes some getting used to but the results are worth the effort...
Here's his build thread....
https://www.smokingmeatforums.com/threads/short-fat-120-gallon-build.238321/page-7#post-1641495
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