The Protribution spec really caught my eye when it first came out; ever since way back in the day (pre-1.8, when my main was still a Paladin) I enjoyed seeing classes getting creative and acting outside their roles. Back then it was a Grand Marshal Paladin who was specced Protection and using a two-hander. Basically his combination of a ton of defensive stats, plus multiple stuns (this was when Repentance was the Protection final ability) allowed him to outlast any opponents. The guy was a great Paladin anyway; cleansing his allies, using Hand of Freedom (well, Blessing back then) and Hand of Protection (again, BoP then) liberally on himself or his friends, and mowing down 3-4 opponents at a time. Gosh I must have watched that video of him in Blackrock Mountain dozens of times.
So anyway, Protribution is, in my mind, the spiritual successor to that pre-1.8 Paladin style. But I can't figure out if it ONLY works at 80. No doubt it works BEST then, but could you level as Protribution before then? My Paladin is on the cusp of 69 right now, and Retribution's tree is all but complete... and I see no good use for my other talents points before cap.
So I was looking at Protribution builds, specifically http://www.wowhead.com/talent#sZVG0AMzghsIufdVf0dbc:RjLczV
Three obvious problems come to mind:
1. Divine Plea isn't available until level 71.
2. Shield of Righteousness isn't available until level 75.
3. Sacred Shield isn't available until 80.
Which means I basically get the base defensive skills of a Protection Paladin, but my mana regeneration and offensive capabilities are limited, and I don't get Sacred Shield to absorb some damage and help heal myself in a pinch. So my attacks are limited to auto-attacking, judging, holy shield (which is more defensive and expensive to keep up), avenger's shield every 30 seconds, and Hammer of the Righteous every 6 seconds. And my mana will run out quick.
I think I'm answering my own question here...
But has anyone tried leveling like that, say after level 70? I would do a mix of questing and BGs; right now I'm Retribution and I love the self-heals, but my attacks seem a little low and I feel too squishy in BGs. For questing it's great, no downtime, tear through stuff. Just looking to mix it up a bit.