Spartan Mora regiments at Battle of Plataea

[PMBardunias]

In fact, virtually all modern armies, and for hundreds of years, have followed this system pioneered in Sparta. The Officers, and also the senior N.C.O's invariably "mess" ( eat and socialise) in separate 'syssitions'/messes from the men.

A common mistake for those who've seen the elephant is to assume that all large quadrapeds are elephants! hock: This situation is not so clearly analogous to the modern officer/GI split. It would be more like a group of officers asked to lead men who had been officers, perhaps superior officers, who were subsequently busted in rank. This would be an akward system at best. The modern "officer class" began as just that, a seperate class, practically a different species, endorsed by God. It is a common trope of novels that an officer who comes up from the ranks is not good for morale- poor Richard Sharpe. The reverse is surely as true. Men who have been kicked out of the officer's club or whose father's were, are less likely to follow happily.

The line of reasoning you describe above might well hold true for enfranchised helots and even Periokoi who might strive for service just as strongly as African- and Native- Americans did or any of the Colonial troops raised by England.