The question of is he better suited for 800m or 1500m needs more info. Are we asking what he thinks is his best chance for a stronger PR, or better chance to get a medal?
The 800m is enough of an all-out race that you can rarely medal without running 1:44-mid.
The 1500m, on the other hand, could be anywhere from 3:32-3:35 for a medal.
The 1500m has got to be more attractive to a 1:44-1:45 guy with a 3:35 PR.
I think a lot of you are right, that if RA focuses on the 800m, his times will look better at the 800m distance than 1500m. Maybe he ends up a 1:43.6 / 3:33.5 guy?
But I think he and his coaches are wise in shooting for a podium rather than fast times.