[jere]

Just noting some oddities/extras:
Most blessings base threat = level gained (20 for BoK, 79 for BoM (highest rank))
Buffing BoW generates no threat for some reason.

BoSanc is all kinds of wierd
Blizzard API gives:
BoS => 13871
GBoS => 22022

BoS is learned at level 30 => 3000*1.9*1.43 = 8151
GBoS is learned at level 60 => 6000*1.9*1.43 = 16302

Subtracting both of these from the recorded values nets a difference of 5720 (in both cases)

5720/1.43 = 4000

So it seems like there is some "non-holy" portion of BoS buffing. Not sure what it is yet. I tried taking off gear to see if different levels of stamina affected the number, but that didn't seem to change anything.

So BoS threat is level*1.9*1.43 + 40*1.43

Wierdness.

[jere]

Just some quick notes for reference on BoSanc:

Measured in game, the threat values for it were
BoSanc ==> 134.42
GBoSanc ==> 211.64

If you divide through by the threat modifiers, you get:
BoSanc ==> 134.42/(1.8*1.43) = 52.2222
GBoSanc ==> 211.64/(1.8*1.43) = 82.2222

Those values seemed odd to me since all the seals, the hand spells, and all blessings but BoW had base threat = level learned.

BoS is learned at level 30 (21 point talent). The greater version is learned at level 60.

30*1.8*1.43 = 77.22
60*1.8*1.43 = 154.44

Subtracting those out from the measured values gives:
BoSanc ==> 134.42-77.22 = 57.2
GBoSanc ==> 211.64-154.44 = 57.2

Which is interesting since they both have the same left over value. More interesting is when I divide it by 1.43 (baked in salv):
57.2/1.43 = 40

That number isn't evenly divisible by 1.8, so that leads me to believe that Blessing of Sanctuary has two separate threat components:
A holy component = level learned
A non-holy component = something else equal to 40

While odd, this isn't the only spell that does that. Hammer of Justice also has two components: The stun (holy) and the interrupt (non-holy).