The gigleur or gicleur restricts the rate of water flow into the dispersion block. This means it takes longer to fill up the cavity above the puck, thereby giving a form of preinfusion.
Your description of the water path in the Piero cap is correct, but you do still have a 3 way solenoid, it is just built into the cap. This means you can still back flush, etc. This is via the clear pipe you added leading to your waste water box.




