Sockets/Increased Item Levels are not tertiary, but an entirely different bonus. From the way I understand it, you can get a piece that has a Tertiary stat (ATM, its Lifesteal, Movement Speed, Cleave, Indestructible), and/or a gem socket, and/or warforged, with any possible combination of the 3 (just 1, 2, all 3, tertiary being random, ect.
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The various Amp trinkets will most likely have some sort of system that will make them degrade with level- if not turned into a rating, then it'll steadily get worse as you level through one way or another.