Military prestige classes, feedback please

[Bobitron]

Can someone help me out here please, I thought that Ranger training was something you could do without ending up in a Ranger unit. And that is was meant for small unit leaders, and that you learned survival, creative leadership, endurance, ... during that course.
Is that correct, or did I miss the train?

I got some more clarification on this in an email.

Absolutely, but only if you are of a certain MOS and if the unit is
authorized slots. For example, any infantryman in the 82nd could go to
Ranger school, but they had to be recommended by leadership and there had to
be slots at Ranger school, so the high-speed troops went first. The chance
for a particular MOS being authorized to attend decreases as you move
further away from Combat MOSs. I'm not sure about combat support units, but
Signal is combat service support, and there was only one short time period
during my enlistment that they were allowing signal soldiers to go to Ranger
school. In a combat MOS, you can also volunteer for Ranger school before
you even get to your permanent station. Your success or failure could
determine what unit you became assigned to. Also, most (if not all) units
require that you attend a pre-ranger course, for obvious reasons. Many
soldiers among the 82nd Infantry were Rangers, and a tab was a requirement
for promotion to E7 (or possibly E8).