Socketing for smaller bonuses?

[Carty]

As a tank reforging and gemming for mastery before parry/dodge, should I stick a mastery stamina gem in a +10parry/dodge socket? Would it be worth it? Or just stick with the stamina gem?

[Sobegreen]

Ignore the bonus unless its going to give you the same as if you went for a solid socket.

For example:
Armor has Two sockets and the bonus is +20 stam. You could lose the bonus and put a +40 stam gem in there but if you put a +20 stam +40 mastery and got the bonus then you still get 40 stam and +20 mastery. I ignore all dodge/parry bonuses. Basically if the bonus is stat +20 and you want that stat your better off to use a double +20 stat gem to get the bonus.

[Muraza]

Mastery in yellow sockets
Mastery + Stam in green sockets Probably how I would do it.
Stamina in blue sockets
Parry+Mastery in red sockets

[vaajtswv]

Which pieces have green sockets btw?