I think it's difficult to say. As far as fairness goes, I'd say that there needs to be a level of realism and ability to detect the person hiding, however we see in numerous cases where stealth is pretty much used to vanish into thin air.
For example:
All these things considered I'd say the game lore treats Hide as being a form of invisibility more or less. Think perhaps something akin to Prism Powder from FFXI, the Rogue/Ninja is capable of using Aether to bend light around them and turn them invisible, though perhaps to prevent being completely undetectable it would work similar to the cloaking device the Predator uses, causing the user to shimmer faintly when they move.
One thing to keep in mind is that there are some mobs immune to Hide, typically creatures that use non-visual methods of aggro, so it could easily be said that a keen sense of hearing or smell could defeat a skilled sneaker.
For example:
All these things considered I'd say the game lore treats Hide as being a form of invisibility more or less. Think perhaps something akin to Prism Powder from FFXI, the Rogue/Ninja is capable of using Aether to bend light around them and turn them invisible, though perhaps to prevent being completely undetectable it would work similar to the cloaking device the Predator uses, causing the user to shimmer faintly when they move.
One thing to keep in mind is that there are some mobs immune to Hide, typically creatures that use non-visual methods of aggro, so it could easily be said that a keen sense of hearing or smell could defeat a skilled sneaker.