Not true. Intellect is not > 2 of our major secondary stats. It isn't a blow out but close. I added a build to my chart to show the difference. While doing so I found a typo in my formula's and corrected them which unfortunatly changed some things. I didnt like how the scaling came out and now I know why it seemed off. Anyway:
Here are the major changes:
Haste does indeed scale well with EF and going from 22% to 41% haste (in exchange for Mastery) is an 8%-10% gain in effective HPS. It is also 16.5% more expensive.
Hitting the 25% or 35% EF break points does give you a small bump in HPS but there is an upward trend in HPS with more Haste anyway.
Sacred Shield does scale with Haste but not nearly as well as EF. Hitting the 30% haste break point is about a 5% gain in HPS but going beyond or further below has little effect on output.
Swapping secondary stats for intellect is a small loss in HPS. It is not a huge loss but 1 intellect does not equal 2 mastery or haste and thus yellow gems > orange gems. But ultimately it will be Purple/Green gems that you may go with depending on how much spirit you want.
SH spec without Spirit for stacked fight still has great output with low mana cost.