In the case of PLD, this is because the PLD is busy tanking. A DPS with clemency would have more opportunities to use it (though, as I've said, you'd need to tie it to some mechanic to limit/control its use).
I'm not sure where you get that I'm asking for a "true" hybrid. I know well enough that it wouldn't work in this game. My argument was that you can't base utility on whether it's used all the time. I could take it a step further and say that at that point it's no longer utility, but a rotational ability.True hybrids don't work in this game. Your opinion is your own, of course, and valid as far as that goes, but there's nothing in this particular game thus far that supports a true hybrid class being successful unless you want to consider SCH one.
Now I'm convinced you're not understanding the other side of this conversation. No one is asking for a healing DPS. What is being asked for is some limited utility that involves healing. Firstly because it fits the concept of the job (RDM being a combination of swordplay, white magic and black magic) and second because it could prove useful in cases where things start to go badly but at a notable cost to the RDM.I've already covered how an oGCD action that happens to heal someone wouldn't be horrible (even if it most likely wouldn't be very useful), but I wouldn't want to see actions like that become the focus or theme of a DPS Job, because no one needs a healing DPS. That's more or less my point.
I'd personally still want the job to focus on DPS and would expect the bulk of the skills to be meant for that. If you need examples of what I was hoping to see with RDM, I'll point to WoW's enhancement shaman and retribution paladin, since those are actual "hybrids" that focus on DPS but have utility built into them; both fight in melee range (hint hint, SE), both can spot heal but quickly consume resources when doing so (which means you're likely not using heals but are there if shit hits the fan), both have some form of party/raid buffs, and the latter has the equivalent of Benediction but better and a cooldown that makes one party member immune to physical damage.