Ok, lots 'o questions:
To Blue Cloud: That's a Screw your seeing, holds the heater core together. As far as blocking the passages, yes if you do that then air will get in from other places. we actually see it coming in from the front seam of the heater core more than from the electronics area. I would like to seal these better, but the manufacturing tolerances in this area were a problem. As long as you don't block the air inlet holes though, it will still pull air from the air intake as intended.
To Stu: The stainless heater heats the bullet directly thru conduction. It also heats the air as it passes thru the air pathway built into the heater core before it enters the bullet. This way we get a combo convection/conduction heating in both the Pinnacle and Pinnacle Pro. Originally we were after using full convection and no conduction, unfortunately the power required to do this is out of the realm of possibility in a portable. This is why you only will see true convection coming from a desktop that has access to 115v AC.