Crankcase breather question

While expensive, this is where a vacuum pump starts to make a lot of sense.

I'd also like know, if anyone can answer it, why you can run an evac system if you run mufflers. Also, do glasspacks count as mufflers?

I have been playing w/ the pcv system some. I think the breather to carb hose deal will pull more out of the engine than we realize.
All street hemi`s came w/ a pcv on the drivers side and a breather hose to air cleaner on the pass. side . "Good enough for me !"
I just recently rigged up a oil mist catch can , because I had the junk laying around, it has a site tube to check oil level . Altho I haven't had any problems in that area , or any oil consumption , or blow by on the valve covers with just a breather on one side , will probly remove it after a while.
What I do wonder is , what effect my 6 pack scoop will have on the pass. side vent/breather to air cleaner deal. Any thots on that ??