One hand weapon specialization increases
all damage you do when you've got sword+board equipped. Holy Shield, Consc, Judgements, everything. It's a common misconception.
1HWS should be read as "+5% damage while you're tanking." 1 point in 1HWS increases your threat much much more than maxing imp ret aura.
To the person above who argued for Divine Intellect: 400 mana is the returns off a 4k heal, once, for an entire fight. If you don't need the heal, you outgear the content and can just swap in gear with Int; if you do need the heal, the talent's wasted. Ask your healers how stressful it is to throw three Flash of Lights or a couple of Renews on you; it won't be an imposition.

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Sweeney: 70 Paladin, Runetotem