How does Mind of Steel perk work?

[Cent]

Does Mind of Steel still require the marine to be entered into the Psychiatric Care Unit or will he recover on his own as long as he isn't deployed to combat? The phrasing seems to suggest he "automatically" does it, yet the PSU panel displays his mind of steel perk and acknowledges his reduced recovery time.

[Eqqsquizitine Buble-Schwinslow]

It's automatic.

The reason the PCU shows the days remaining is not because there's any reduction in time spent per trauma point, it's the number of days remaining before the trauma disappears on its own, without ever needing to actually put your marine in the PCU.

What I really want to know is, if I have a level 2 or 3 trauma, does it remove all of the levels, or just one at a time?

[Sotnik]

Does it remove the traumas got before the attribute is acquired?

[Narrowmind]

I think the attribute is simply related to how many points of trauma there has been accrued, right? So if there is no trauma points left, there is no attribute. Or am I wrong?