Please explain what's wrong with my dual catch can setup. It's no different than all other dual catch can setups out there for boosted engines, aside from application-specific mounting/routing details.

It is simply returning the PCV system to a fully closed, functioning PCV system like stock (PCV valve connected to the intake manifold, breather port connected to the air filter area). The only difference is that I add a catch can inline on each side of the system.

Yes, oil vapors do come through the breather hose. This happens when on boost. Piston blowby has to go somewhere, and the crankcase breather is the place it goes. I don't want those vapors going back into my intake, coating the inside of my intercooler (making it less efficient) and lowering the effective octane of the fuel while on boost. I also don't want it to vent to atmosphere, because it stinks (that's what it does right now). Catch can is the solution (specifically a catch can with an oil separator in it).