Strength line has two CAs- Torporous Strike and Traumatic Swipe- that are intensely useful in raids.
As for str/agi str/wis... well, two of our raid swashies are myself (str/wis), another (str/agi) and we parse roughly evens most of the time. The MT group swash is agi/wis and can parse 20-40% higher in given situations, though this is a little to do with gear and a lot to do with his competitive nature 
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Rahael, Purity Nagafen