Re: Janeway's Decision to Kill Tuvix
"The Enemy Within" specifically states Evil Kirk is dying, so presumably Good Kirk is too. Before medical treatment cures their "mental illnesses", they'd both be dead. Spock should have assumed command immediately, as soon as it was evident Good Kirk was having reasoning problems.
And that 2 halves of the same person can't survive alone is seen once again at the end of "Faces."
Akoochimoya, my indigenous ass.