What Do Air Jets affect on Mikuni VMs if there is a Primary Type NJ?

I know Bleed type (175 P-x) the air comes in from the Air Jet and can atomize fuel through the needle jet because there's little holes in it, but for say, the Dave F carb mod (169 P-x (VM30s), 159 P-x (VM28s)) , what does enlarging the Air Jet do? Where does that air go since it can't enter the Needle Jet if it's a Primary Type? (no little holes)

My understanding is that enlarging the air jet (in the intake side of the carb throat) will reduce the amount of fuel sucked up by the main jet. So if you need a 182.5 main jet and only 180 or 185 are available, you can use the 185 and enlarge the air jet to get things dialed in. Although, I'm not sure of the exact ratio and how everything relates. My understanding is pretty basic.

Charles.

The air jet acts to assist atomization at high speed (3/4 to full) by and to help in high speed fuel metering.

they create better power lower in the curve of air flow and rpm