Question regarding that rubber deflector the K&N air filters come with that replace the OEM foam one in the airbox: WHAT'S IT DO?

Is it there to slow the airflow under certain circumstances? If I've got a Yosh RS-3 exhaust, a 4-1 manifold, and a Dynojet Stage 2 kit, should I ditch the deflector in favor of increased airflow?

I noticed the Stage 2 kit mentions using it in conjunction with a "modified airbox," but i can't find much info on F3 airbox mods. Am I barking up the wrong tree here?

 

Come on, guys! You'll go on for 12 pages about how to wave at another rider, but not a single response to this?

 

Here's another bump.