All I can say to that is this: The next time I have to make a combat drop, I want the men on my flanks to be graduates of Camp Currie or its Siberian equivalent. Otherwise I’ll refuse to enter the capsule. (R.A. Heinlein, "Starship Troopers")
This paragraph makes it sound like the entire Earth only has 2 boot camps for Mobile Infantry - with another one added later on in-universe that Rico's father went through:
"Well, I trained at Camp San Martin—" "Huh? Not Currie?"
Yet, MI seems to be the main grunt branch of Earth military engaged in a pretty wide-scale war, with at least tens of thousands if not millions of troopers.
Since every MI would go through one of those boot camps, this seems to limit the army size greatly; a single graduating class is less than 50:
What the sweat-down meant, really, was much more personal instruction; we had more corporal-instructors than we had squads and Sergeant Zim, with only fifty men on his mind instead of the two hundred and sixty he had started with, kept his Argus eyes on each one of us all the time -- even when he wasn't there. At least, if you goofed, it turned out he was standing right behind you.
This seems like a contradiction. Did I get my details wrong somehow? Or did RAH explain the contradiction away in some other quote?
UPDATE: Found this quote about camp sizes - the initial quote about 260 recruits per Sergeant Zim discounted the fact that there were more than one company in the camp (Zim was "H company commander" so there were other companies):
I did Basic at Camp Arthur Currie on the northern prairies, along with a couple of thousand other victims
Well, the Third Regiment was much smaller now, too less than four hundred whereas we had started out with more than two thousand. H Company was now organized as a single platoon and the battalion paraded as if it were a company. But we were still called "H Company" and Zim was "Company Commander," not platoon leader.
Still, "couple of thousand" seems like less than 5000, and given the attrition rate of 1:5 in the original quote, that means a graduating class is less than 1000. The numbers still don't seem to add up as far as staffing the entire MI from just 2 boot camps.