The various class guides I use recommend these Prot Pally priorities and stat weights:
- Noxxic: Stamina > Hit (7.5%) > Expertise (15%) > Haste > Mastery > Parry > Dodge
- WoW Heroes: Stamina > Hit (7.5%) >= Expertise (15%) > Mastery > Haste > Parry >= Dodge
- Icy-Veins: Stamina (until you have enough,) > Hit 7.5% > Expertise 15% > Mastery > Haste
- WoW Reforge: Hit 2550 cap, Expertise 5100 cap, Mastery 1.04, Hit 0.65, Expertise 0.43, Haste 0.41, Parry 0.35, Dodge 0.35
- Elitist Jerks/Theck (of Sacred Duty)(via Ask Mr Robot): (C/Ma) Stamina 1.5, Hit 1.1, Expertise 1.09, Armor 1, Mastery 1, Haste 0.8, Strength, 0.6, Parry 0.5, Dodge 0.5
There is also consensus that capping Hit and hardcapping Expertise is one of the viable gearing strategies, and possibly best. One of my operating principles of playing a Paladin is generating and spending as Holy Power as possible. For this reason, I cap in order to be sure that every Holy Power generator lands.
I began this expansion by gemming and enchanting for Hit and Expertise, equipping a Ghost Iron Dragonling (ilevel 450) with Hit and Expertise cogwheels, and using Expertise food and elixirs. After capping Hit and Expertise without elixirs or food, I switched to the Stamina options. Now I've begun to shift as many as possible of my gems and enchants to Stamina options while maintaining caps. My ilevel being 481, I still have some ways to go.
After Stamina and the Hit and Expertise caps, the question turns to Haste vs. Mastery vs. Dodge/Parry. In patch 5.2, the traditional tank stats, Dodge and Parry, are just now useful as Holy Power generators, more so in situations with many hits coming in. However, stacking avoidance still does not sim better than Mastery, Haste, or mixed builds.
Haste generates more Holy Power, resulting in greater uptime of Shield of the Righteous. Mastery makes each SotR more powerful. A mixed approach is possible as well. I prioritize Mastery since while I'm now fairly well practiced with using the SotR buff, there's still room for improvement. If in the future some progression boss fight were more suited to a higher uptime vs. a stronger buff, I'll try reforging for haste, but before I can fully use that strategy, I think I should be at least 95% on using available Holy Power generators. I might be already, but I'd have to review a log. The reason for my hesitation to stack Mastery is that missed Holy Power generators, i.e. not using one immediately after is comes off cooldown, greatly reduce the advantage of Haste.