The last time I tried simming out all of my stat weights(int, sp, spirit, hit, haste mastery, crit) and scaling them, it actually gave me a result with hit and spirit having different stat weights which seemed weird. Also, it put haste significantly above mastery. However if I just analyze haste and mastery on scaling it puts mastery ahead of haste. I was wondering what might be causing some of these results as they seem a bit odd to me. this is my armory if someone else might want to give it a go and see if they get the same results.
Haste is unreliable in many tools. They usually add 1 and measure the difference. It can fluctuate wildly, and adding 1 haste can reduce DPS in odd cases, and increase it massively in others.
You'll find the graph is overall better for that kind of analysis.