The specific proposals, IIRC, were actually less about warfighting (ugly, neologism but we'll stick with it) and more about juggling personalle and force structure to an acceptable level (i.e., in terms of manning/funding/and that old bogey "the Treasury"). It was a way of justifying maintaing those capabilites rather than, say, have some suit/tie type turn up and say "you don't need tanks!" Jumbling the arms up like that was meant to "sell" combined arms (i.e., "we still need at least a bit of everything" to "donors".