I'm having issues with your interpretation of Fist of the Forest. I was excited about the Dice Size increase, but the more I read into it the more I'm convinced it doesn't work like that.
It states:
Unarmed Damage (Ex): Your unarmed attacks deal more damage than usual. At 1st level, you deal ld8 points of damage with each unarmed strike. When you attain 3rd level, this damage increases to 1d10 points. See the monk class feature (PH 41). If your unarmed attack already deals this amount of damage, increase the base damage to the next step indicated on the monk class table.
A quick look at the monk damage tables will clearly show 1d8 -> 1d10 as natural progression for a medium character advancing in monk levels (as noted by the FotF table), not across dice sizes.
Cru proposed this explanation
My reading:
A Monk 8 with 1d10 unarmed strike damage enters FotF.
At FotF1, her unarmed damage already deals more than 1d8, therefore, the damage increases to next step: 2d6.
At FotF3, again, her damage increases to the next step indicated on the monk class table: 2d8.
But, here is the sample build for a FotF:
SORAG, WARDEN OF THE GREEN CR 9
Female human monk 6/fist of the forest 3
...
Feats: Combat Expertise, Combat Reflexes8, Dodge, Great
Fortitude, Improved Disarm8, Improved Unarmed Strike8,
Mobility, Power Attack, Stunning Fist8
...
Melee unarmed strike +12/+7 (2d6+5) or Melee unarmed strike +11/+11/+6 (2d6+5) with flurry of
blows
Her base Monk6 unarmed damage is 1d8. She has all 3 levels of FotF, so she has moved two steps in the table, going 1d8 -> 1d10 ->
2d6. If her dice size had increased, she would have moved 1d8 ->
2d6 ->3d6. This could only be possible if the ability where to increase your size at level 1 and grant you no other benefit at level 3.
To me, it seems that FotF is a way to advance 2 full steps on the Monk unarmed progression in just 3 levels; more in line with the Monk's Belt or SUS, and not like INA.
I really hope I'm wrong u.u