It is located on the side of the block under the intake manifold, it is where the PCV valve attaches. It is really only a couple of baffles that cause the air flow leaving the block via the PCV to change direction a couple of times which causes oil in suspension in the air to drop out back into the pan. It is nothing new they have been using baffles to prevent oil from being sucked up by the PCV valve since they started putting PCV systems on engines in the 60s.
Radium makes a replacement for the stock one that is a much better design. It has many more direction changes to encourage the oil to drop out of suspension.
FWIW, when I built the 360 in my Barracuda I put on a set of valve covers that did not have any baffling infront of where the PCV attached and within a couple of days I had an oily mess at the PCV valve and at the other end of the hose where it connected to the intake manifold. Fortunately those valve covers had bosses for a baffle and took the one from the stock covers and installed it. 15 years and 70k miles latter no mess.
The baffling helps, a catch can is better but until someone comes up with a system that is not routing crank case fumes back into the engine you will always have some level of carbon build up.
Saw an write up where a guy had a very expensive ($500+) catch can that had multiple stages of baffling on his 3.5 Ecoboost F150. He was interested in how much got through and bought a UPR can and put it in series after the expensive one and still caught oil. He reversed them and the UPR caught about the same as the expensive one did when it was first.
The question is where is the point of diminishing returns.