This is a silly discussion.
Face it, the best enchant on gloves is going to highly depend on a number of factors:
1) What tank class you play
2) What tanking role (MT/OT)
3) What content your tanking
4) What your current gear level is at
5) What changes Blizzard makes
6) Personal Preference.
Currently, due to SoL threat and double ShoR, paladin threat is thru the roof. That will change in patch 3.08 and we have yet to see what the full impact will be on our TPS.
If your just tanking heroics, then you won't require extra threat, so you will probably focus on a DPS or EH enchant.
Which one you pick will depend on your gear.
If your stamina is low, then a stamina enchant may win out.
I generally rate armor enchants low as an option since they do not benefit from class magnifiers.
If your happy with your EH and want to generate more threat/dps, then number crunching shows clearly that hit rating has a bigger effect on paladin DPS and threat than expertise does, so if your hit rating is low, then Precision may well win out.
If you want to block a bit more and increase AP then its Str.
BUT...if you are tanking Malygos, then its all about not threat-capping your DPS in phase 1, and building a huge threat lead, so for current high end content, Armsman wins out.
2% threat increase is greater than anything else.
As Ulduar and the rest of the end-game content comes out, I fully believe that all tanks will indeed be challenged to generate enough threat to not cap their DPS.
Malygos is probably just a prelude of things to come.
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Garath Lvl 80 Paladin, Gorefiend