And I've played her a lot as retribution as well, ret has been my default off-spec for some time, and my main spec for the old girl in PvP, too. It's a great fun spec to play, if a tad irritating as far as prolonged damage goes.
But, every now and then, I get a hankering to heal with her. This first happened when I got to level 80, got to know the dungeons, and decided that that was the very best moment to have a go at healing for the first time on my paladin. I off-specced myself into holy, got my hands on some gear, and got straight into a normal dungeon. It was a disaster. I respecced back to ret almost immediately afterwards, and sold the gear.
Then, again, at 85, I realized that, along with shaman and priests, which I'd been healing on for some time, paladins made pretty decent arena healers. So off I went, got the spec, got the gear, got a team-mate, and went into arenas. It was almost as disastrous as the time before, but I stuck at it a little longer before deciding that I was still a dreadful paladin healer. I sold the gear.
And now, at 90, here I am again. I've just specced into holy. I've got myself a holy set, a mixture of adventurers' gear and drops. I've set up Clique. And I'm scared. Paladin healing is something I've tried time and time again to conquer, and never succeeded at. Perhaps it's because I think I'm a good tank, and a decent ret that my holy hopelessness feels so awful, or because I think I'm alright at priest and shaman healing.
But I can't let it lie. I have to keep chasing that white whale, to the last I grapple with it. What's your white whale? What have you failed at in the past but can't leave alone? Anything at all, not just specs!