[throw10920]

That's really neat - being able to reduce your sensitivity to CO2 if it's overly high sounds useful.

Do you know if it's possible to do this to dangerous levels - that is, make your body so tolerant of high CO2 levels in your blood that you unconsciously adopt a dangerously high blood-CO2 level as your default state?

[codethief]

I'm afraid I don't know. You would have to talk about that to people experienced in free diving etc.