posetcay: Inside liberties don't count for black if black is trying to kill anyway, you can turn the tail into a cutting group to avoid the situation where black is trying to kill.
posetcay: Black can kill opponent by sacrificing the tail, so it should be unsettled.
d4rkm4tter: By sacrificing the tail, black looses the eye and the inside liberties are gained by white. So is is -2 +2 liberties - no change. There is also no ko. I'm still thinking about what happens if black has the liberty advantage, but I tend to say the problem is ok right now.
Inside liberties don't count for black if black is trying to kill anyway, you can turn the tail into a cutting group to avoid the situation where black is trying to kill.