Quite frankly, it
should be bottom-up for rallying. The way that SSI implemented it has
always appeared counter to logic to me (IMHO!

.
It does mean that the platoon commander (and above) can get 'drained off' by subordinates even if needing some rally themselves (pinned etc). So a human user has to check for pinned or worse command elements before doing his rally rounds (I do anyway). The AI however....
(I have no idea how difficult it would be to reverse it so that the platoon commander's rally is only used
after the section corporal runs out of steam, but will try to investigate that this winter.)
Andy