It's definitely plausible; we know neurological conditions can cause that (one character in A Call To Arms is rendered unable to synch with a BattleMech-grade neurohelmet due to a TBI, though she can still use an IndustrialMech-grade one). However, I was more referring to why Caleb got shifted into armour specifically; we don't know on that count, and I'd have to check Sword of Sedition but IIRC Julian mentions Caleb being "rushed through" training and shuffled off to honourary command of the Syrtis Avengers' tank brigade with undue haste.
Might just be as simple as armour command training having the quickest training cycle and Harrison just wanting things done with, for all we know.
Affluenza, and he probably couldn't medical for Flight school even with a waiver.
LOOK at the man's behaviors-and don't use Schizophrenic episodes as an excuse, look at how he applies his base assumptions.
Here's how it most likely went down;
Caleb was Harrison's darling son, maybe the only son he
could get from his wife (and/or concubines) and the Crown Prince of the Federated Suns as well.
So Caleb is raised like little lord Fauntleroy, gets what he wants, when he wants it, other people get the discipline (maybe the Feddies resurrected that ancient feudal practice of 'The Whipping boy', which might explain his sadism to an extent).
Well, he gets to that age where you test for 'mechwarrior ability (the ability to synch a neurohelmet) and shock-of-shocks!! He can't make it work, maybe even picked up a bit of a feedback injury from trying.
This obviously DQ's him from 'mechs, but it also DQ'q him from Aviation, and maybe his reflexes underline it.
But! He's the Royal Heir!!
and he's
soft, sensitive to slights, not infantry material.
Where do you stick him?
In a Tank, with a crew cross-trained as bodyguards, because the First Prince
Must have a military background *(it's the law!) and Armor has, at least,
some cache' above Infantry.
(and it's not like the FSN has a Naval command that doesn't demand fighter branch first.)
Ergo, they make him a tanker and give him a crew that will cover his ass both in the field, and cover for his...excesses at home (because Danai was probably NOT the first girl who said 'no' and he just went ahead and did to her anyway.)
Which is also why, once it sank in just what kind of 'man' Caleb was, Harry decided he'd rather have Julian on the throne.
