Men who were prone to alternative/extreme states of consciousness would have been better able to summon up the wild emotions necessary for savagery and violence, making them better fighters and hence giving them better mating prospects.
If they've even lived long enough, no absolutely not. Unless you think someone who is routinely depressed is 'vigilant'.
[Hypo]mania is not the primary state of a bipolar patient. Can't speak to schizophrenia, but for those I've seen with that illness, functioning isn't their primary state, either.
Thinking mania can be controlled like an on-off switch.
Why even bother posting?
And someone who experiences mania indicates an uncontrolled illness. Depression and mania prevent normal functioning. You seem to believe an unmedicated bipolar individual is a functional individual with some inkling of rational thought that could 'go into battle with no fear'.
If you don't know, don't post. And you don't know.
I don't know where you are getting the notion that I am saying that mania is rational or controllable. I was speculating based on personal experience around high stress situations. I do not understand why you are choosing to attack the notion that there could be evolutionarily advantageous benefits conferred upon the group.
Edit: we agree that I am speculating. I disagree with you that I have no right to speculate