Ghost thread, but timely. There was an article about just this in one of the recent trade mags (either the USATriathlon one or perhaps Triathlete), although it was more on the accepting a canister of CO2 or the like from a fellow racer.
They quoted the above rules (though not in the context of drafting) and basically said they're trying to get to a more common sense approach, namely that if someone tosses you a GU/tube/CO2 cartridge, etc. it's fine - AS LONG AS they're not in the race specifically to help you (a rolling spare parts machine) OR that by giving you assistance it will impede their own chances of finishing as best they can (so, even slowing them down materially is not cool with the rule).
Applied to this case, if said dude was sitting up to ensure he didn't drop said elite, he'd be violating the second part of the rule (methinks).
And, apparently, the whole no-drafting rule doesn't apply to at least one HIM distance Iron branded event I did last summer, where on my way back on the out and back bike course I saw several HUGE samba lines of cyclists on each others' wheels blasting along...