I have discussed this with a number of GMs but there's been no consistency on the matter. So I bring it here in the hope there is a more Official ruling answer. I'm including a number of variables to see where and how they are applied/effected by these abilities. All skill descriptions are given at the bottom.
If you do not agree with any of the following examples please explain and give a skill stat example using the same calculations given below.
-The Debate- The core of the issue (from what I've been hearing) is how Versatile Performance is supposed to be used when handling skill Checks. These are the best examples I have been given thus far.
A: No, Art of Deception doesn't stack with Versatile Performance. You are using the skill "in place of its associated skill's bonus". Bonuses to that Perform will apply to VP, but any bonuses to the original skill do not. If you wish to use original bonuses you must use the skill normally.
B: Yes, Art of Deception does stack with Versatile Performance because you are using a bonus to to that skills "Check". When substituting you do not use any "check" bonuses of the Perform skill since you are not doing a perform check. VP is only using rank+mod+CS bonuses. Any bonus to the original "skill check" applies to the total.
C: Yes, Art of Deception does stack with Versatile Performance. VP says to use the "total Perform skill bonus", so you will apply any bonuses to the Perform skill. VP is using a alternate method to complete the same task (Ex: You are still Bluffing, but you utilize your Acting skills). Thus any bonus that applies to the original check roll is added to the total.
[Character Example] 8 Bard / 3 Spy (Total level = 11), Charisma 17 (+4) Modifier, Bluff: Rank 7, Disguise: Rank 7, Perform (Act): Rank 11, Perform (Oratory): Rank 11
Total Bluff: (19) = 7(ranks) + 4(Cha) + 3(Class Skill) + 2(Deceitful) + 3(Art of Deception)
Total Disguise: (19) = 7(ranks) + 4(Cha) + 3(Class Skill) + 2(Deceitful) + 3(Art of Deception)
Total Perform [Act]: (30) = 11(ranks) + 4(Cha) + 3(Class Skill) + 6(Skill Focus) + 4(Prodigy) + 2(Savant)
So if rolling a Disguise check:
Example A - Use VP (Total Act) -or- use Total Bluff: (30) -or- (19) / (29) Disguise Self spell, +2 with Disguise Kit
Example B - Use VP with Bluff Check modifiers only: 11(ranks Act) + 4(Cha) + 3(Class Skill) + 2(Deceitful) + 3(Art of Deception) = (23) / (33) Disguise Self spell, +2 with Disguise Kit
Example C - Use VP (Total Act) and Bluff Check modifiers: 30(Total Act) + 2(Deceitful) + 3(Art of Deception) = (35) / (45) Disguise Self spell, +2 with Disguise Kit
I personally lean toward B or C. I see no reason why the bard cannot benefit from bonuses to the original check. Any help on this is Greatly appreciated.
[Bard 2] Versatile Performance (Ex): At 2nd level, a bard can choose one type of Perform skill. He can use his bonus in that skill in place of his bonus in associated skills. When substituting in this way, the bard uses his total Perform skill bonus, including class skill bonus, in place of its associated skill's bonus, whether or not he has ranks in that skill or if it is a class skill. At 6th level, and every 4 levels thereafter, the bard can select an additional type of Perform to substitute.
The type of Performance being used for this character is: Act (Bluff, Disguise)
[Spy 1] Art of Deception (Ex): A master spy adds her class level to all Bluff, Disguise, and Sense Motive checks.
[Feat] Deceitful: You are skilled at deceiving others, both with the spoken word and with physical disguises.
Benefit: You get a +2 bonus on all Bluff and Disguise skill checks. If you have 10 or more ranks in one of these skills, the bonus increases to +4 for that skill.
[Feat] Skill Focus (Act): Choose a skill. You are particularly adept at that skill.
Benefit: You get a +3 bonus on all checks involving the chosen skill. If you have 10 or more ranks in that skill, this bonus increases to +6.
Special: You can gain this feat multiple times. Its effects do not stack. Each time you take the feat, it applies to a new skill.
[Feat] Prodigy (Act+Oratory): You are naturally skilled at arts, professions, and the acquisition of knowledge.
Benefit: Choose two Craft, Perform, or Profession skills in any combination (two Craft skills, a Craft skill and a Perform skill, and so on). You receive a +2 bonus on checks with these skills. If you have 10 or more ranks in any one of these skills, the bonus increases to +4 for that skill.
Special: You can gain this feat multiple times. Its effects do not stack. Each time you take the feat, it applies to two new skills.
[Social Trait] Savant (Kitharodian Academy): From a very young age, the ability to master performance types has come quite naturally to you.
Benefit: Chose a performance type. (Act) You gain a +2 trait bonus on all Perform checks made using that performance type. Perform is always a class skill for you.
[Item] Disguise Kit: The kit is the perfect tool for disguise and provides a +2 circumstance bonus on Disguise checks. A disguise kit is exhausted after 10 uses.
[1st level Spell] Disguise Self: School illusion (glamer); Level bard 1, sorcerer/wizard 1. Casting Time 1 standard action. Components V, S. Range personal. Target you. Duration 10 min./level (D)
You make yourself—including clothing, armor, weapons, and equipment—look different. You can seem 1 foot shorter or taller, thin, fat, or in between. You cannot change your creature type (although you can appear as another subtype). Otherwise, the extent of the apparent change is up to you. You could add or obscure a minor feature or look like an entirely different person or gender.
The spell does not provide the abilities or mannerisms of the chosen form, nor does it alter the perceived tactile (touch) or audible (sound) properties of you or your equipment. If you use this spell to create a disguise, you get a +10 bonus on the Disguise check. A creature that interacts with the glamer gets a Will save to recognize it as an illusion.
