caz312 - yes, I'm aware of the text you cite, but it's not always as straightforward as that (particularly when it comes to challenging clueless ICC staff - hence asking the board for its collective wisdom..)

Myabe I should clarify my rationale up to this point:

Can't get 3xJ on a direct YYZ-EZE routing (AC only release 2xJ at a time), so we have no option but to go indirect.

So I guess the potential sticking point is YYZ-IAH va YYZ-TPA-IAH with a stopover in IAH.

IIRC, availability for YYZ-IAH for the three of us on the dates we're considering was not looking good at all (in any cabin, for the dates I have in mind) - so my assumption was that a less direct routing should be reasonable.

There seems to be a reasonable amount of flexibility for TATL redemptions (e.g. I booked YYZ-ORD-ZRH-LHR in J for 3 people without any trouble last year) - hence my initial thinking this ain't gonna be too unreasonable a request.