Hey.. thanks for this thread!
I found out that I have been running Fast Healing wrong
SRD said:
Fast Healing
A creature with fast healing can remove 1 lethal hit and 1 nonlethal hit per round per 5 points of fast healing (minimum 1 hit of each type). For example, a vampire spawn has fast healing 2; it can therefore eliminate 1 hit and 1 nonlethal hit per round.
A creature with fast healing may add its fast healing value to Fortitude saves made to become stable when dying. A dying vampire spawn, for example, gets a +2 bonus on its Fortitude saves to become stable.
Which makes this conversation even a bit weirder as there are two specfic mechanical effects. One provides a flat healing of damage per point of fast healing. This ability looks like it could stack as the
Slaved hopes.
The second provides a '+' to Fort saves. This ablity definatly would not stack per the usual stacking rules.
So.. using the RAW,
Slaved's character who gains two versions of Fast Healing 2 would heal 1 point of damage per round and gain a +2 for Fort checks to stabilize
However the OP's character having Fast Healing 5 and gaining an additional Fast Healing 1 would benefit from healing 2 points of damage a round and have +5 to the Fort save...
My suggested Vampire with 8 levels of Warlock + 3 Evolved Undead would only heal 3 points of damage each round...and would not worry about the Fort save to stabilize anyway.
[sidetrek]Slaved, I don't know about you...but to me a challenge is more than just how many hit dice the critter has. I don't often run Vampires against my group unless its in a Ravenloft game...where the group expect to lose 2 or 3 PCs in the couse of an adventure....If Fast Healing 15 was healing 15 points of damage each round as I originally thought...ouch![/sidetrek]
Finally. No. THe designers did not specifically call out in the rules whether Fast Healing stacks or not. There simply is not enough room in the rules book or enough time in the game development process to cover every detail. This is why they publish the principles and design/development stuff...
so that GMs can better interpret the intent and use extrapolation to cover the details
Now that I see how Fast Healing works in RAW, I would have no problem with allowing the ability to stack for the 'healing' portion of it. However there are examples upthread where the ability has not been used as stacking in 'official' material.... so in my game it will continue to not stack {and may continue to heal the amount listed on the ability....

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