The fb piece has the intake from the mouthpiece in the connection below. If it was connected trough the top connection that would change things, but if the intake is that low in the can it might lead to sensible water levels.
Really hope you get your best piece ever with this, because honestly, it is a beauty. But I do believe this one is connected with the bottom connection lower in the can, which in other models, fc-187 and fc-ufo come to mind, did lead to unwanted drinking.