The problem with venting the catch can back into the inlet is that you still allow oil vapour back into the inlet causing octane dilution
Thats the whole point of a catch can mate, when the vented gasses pass through the catch can the vapours are "dropped" in the can to prevent them going into the inlet.
Not 100% efficient, some vapours will still get through, but the majority wont.
Gee in my opinion your set up is wrong. There is nothing in your set up that will remove the vapours from the crankcase into the can. Have you ever had to empty it?
This is my setup, please dont think this is a way of showing how yours is wrong as its different from mine, this is the way I do it.
I use 2 pvc valves so as the valve nearest the inlet mani closes under boost, preventing the can getting pressurised. The valve in its normal place stops anything in the can being sucked back into the crankcase. The breather filter does as it named, its on the other pipe off the rocker, where the standard dump valve hose was connected.
I get an emulsified oil in my catch can, like a melted bar of fudge.
I empty it about every 6 months, the ammount in it varies.