Signet of Mercy - bugged or intentional?

Sometimes when using signet of mercy it only heals the player to close to full hp, doesn't actually revive them... is that intentional? It does seem like the skill itself simply "heals" (when you revive an almost dead ally they revive with very low hp, but an ally who has only recently downed revives with nearly full hp). But is it intentional it sometimes won't revive at all? Or is that a bug?

iirc ,the signet only "heals" downed people and instead of healing 100%, it will only heal 66% in downstead while under the effect of poison.

@"Virdo.1540" said:iirc ,the signet only "heals" downed people and instead of healing 100%, it will only heal 66% in downstead while under the effect of poison.

Thank you, interesting interaction & good to know.