|Mathwei ap Niall|
I'll jump in and state that I'm on the other side of this interpretation. Blindfight appears to be designed to only offset the penalties from concealment and invisibility and not have anything to do with actual blindness. If the feat had a different name this wouldn't (probably) be in question.
Heck even the rules for concealment specifically call out the need for sight to bypass the bonuses from invisibility.
Although invisibility provides total concealment, sighted opponents may still make Perception checks to notice the location of an invisible character.
Here's the basis of the argument that blindfight doesn't help when in darkness, The feat has 3 separate paragraphs on what it does and since they separated them so completely they have to be examined that way.
A). In melee, every time you miss because of concealment (see Combat), you can reroll your miss chance percentile roll one time to see if you actually hit.
Exactly as written when you miss because of the concealment rule roll again once and check if that roll succeeds. No arguments on how this works.
B). An invisible attacker gets no advantages related to hitting you in melee. That is, you don't lose your Dexterity bonus to Armor Class, and the attacker doesn't get the usual +2 bonus for being invisible. The invisible attacker's bonuses do still apply for ranged attacks, however.
The feat specifically calls out the invisible condition and since that is a defined game term it only pertains when the target is under the effects of the invisibility condition. The invisibility condition itself references the blindfight feat and reinforces that it only affects invisible creatures.It doesn't say UNSEEN opponents it specifies INVISIBLE opponents only.
Next the Darkness definition reinforces the assumption that blindfight doesn't help here.
In areas of darkness, creatures without darkvision are effectively blinded.In addition to the obvious effects, a blinded creature has a 50% miss chance in combat (all opponents have total concealment)
It states that the player suffers the blinded condition, it doesn't say treat all opponents as invisible or even unseen just apply the blinded condition to the sufferer. The Blindfight feat specifies it overcomes the invisible condition not the blinded condition.
C). You do not need to make Acrobatics skill checks to move at full speed while blinded.
This is the only reference the feat has to the blinded condition which it calls out as a separate condition from invisible. This is the only thing the feat does when the character is considered blind. This shows that the writers were aware of the Blinded condition and only chose this single affect from that condition to be overcome by this feat. They could have easily said that Blindfight negates all or even just the combat penalties from the blinded condition but they didn't, they chose to only specify this one part of it. what this means is not only doesn't blindfight prevent you from losing your dex bonus in the dark you ALSO suffer all the other penalties that go along with the blinded condition.
Is it a case of bad writing and naming for this feat? Probably but we've had to deal with that before (Prone Shooter I'm looking at you), but in simple RAW terms this feat does NOTHING against the actual Blinded condition.