I'm not disputing anything you said, as others have as well. But every time (even this expansion) when I go to Sim my paladin I get totally different stat weights.
I'm at 539 ilvl with 2pc T15 (I have T16 chest piece, but I'd break my old bonus and gain nothing new).
Armory Link
This is what I get when I sim my toon. Maybe there's something you can see that might be wrong? I'm doing it at full raid buffs/debuffs and 10k iterations and I get the below:
Str 4.71
Crit 2.79 (4.18 when taking 0.50 gem boost)
Haste 2.62 (3.93 when taking 0.50 gem boost)
Mastery 2.46 (3.69 when taking 0.50 gem boost)
I know last tier I was getting Haste > Crit. Now I know why Haste/Mastery are better than Crit, it's just that the sim isn't backing up the same information.
Ok, redid it with 25k iterations and changed player skill to average and see what it said:
Str 4.73
Crit 2.69 (4.03 when taking 0.50 gem boost)
Haste 2.50 (4.00 when taking 0.50 gem boost)
Mastery 2.37 (3.55 when taking 0.50 gem boost)