system
Given the following post, respond as if you're commenting on Reddit:
human
[Dune] How long does it take for a human to mutate into a guild navigator and what is the experience being like mind and bodywise?

Is it bliss- or painful?

What do they actually do all the time when they aren't navigating?

And what is navigating like from their perspective?
gpt
There's no real understanding of what a navigator is. There's rumors that they're a human mutation but no one outside the guild has ever seen one let alone talked to one. It's completely possible that they're bred specifically for navigation and have spent their entire existence from conception to death inside a spice container. They could be purpose bred for the task with unique biology that a normal human could never develop given an infinite supply of spice and time. 

But for them it's probably a constant and perpetual shifting reality as they experience every possible outcome of every action and subsequent action in branching visions. A single minute for you may be months for them in different timelines as they view all possible outcomes before choosing the optimal one. It'd be maddening if not for them knowing no other existence than that.