I expect that downing will save you if you get taken out by a lucky shot or a grenade, but if you wander into the open and get killed by a hailstorm of plasma bolts or a vehicle, your allies won't be able to save you. It'll be interesting if allies get a buff while you're incapacitated. Maybe they can absorb more enemy fire, or their melee can suddenly send a Jackal flying.

Also, the article said that certain weapon types will prevent revival. I guess if you get shot by a Scattershot or Binary Rifle, you disintegrate and no rez for you.