Topic Expertise as caster
Since the release of Mist of Pandaria expertise now also helps casters to get to the hit cap. Since I started gemming and reforging this since you can have both expertise and hit on the same gearpiece and get red socker bonus while gemming for hit rating people have been confused. I have been called several names saying how retarded etc. I am when they actually just isn't informed by this.
It says nowhere in-game (as I have discovered) and it is pretty hard to find information about it both here on forums or other pages. It would be good with in-game tooltip and/or a sticky thread on the forums confirminc it works as hit for casters aswell.
A better statement would be:
"Gemming expertise and hit is a bad idea if you can reach the cap by reforging or enchanting instead."
I'm not up to date with caster stat weights, but at least in my case 1 str < 2 hit/exp, meaning that, as long as I cannot reach cap by reforging, a hit or expertise gem is going to be preferable to gemming strength.
This will change once you reach cap since now gemming hit does not actually provide you with a benefit based on the value of hit below cap, instead it gives you more secondary stat budget when reforging and 2 of any other stat < 1 strength.