Ok, thank you. At least your strength factor agrees with what I'm seeing on ptr unlike the ones I could get elsewhere.
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It's not less than half as strong as our secondaries as such; strength has always been the strongest stat. It's just that you get a budget of 2 secondary stats for every primary stat on gems. As such, strength has to be worth at least double any secondary stat before it's worth gemming pure strength in red sockets. A simple 1.75 multiplier would have done that if the secondaries didn't increase by the same proportion. I didn't see anything to suggest that they did so was going to get busy with the bolds.
I'm still going to assume a haste of at least 40% will be preferable though, accounting for the fact we get proper haste from raid buffs now.