I wonder at how proving a legal path to ending life for anyone (with a lengthy waiting period and multiple psych sessions) would reduce the instances of impromptu suicide. My suspicion is that the availability of a legitimized path to the same result, but with a far less traumatizing method for both the individual and their loved ones, might allow for transitioning people into getting help when that's not the outcome…
IMO there's no way this would ever become any sort of common occurrence, because the state would never willingly give up its human capital on that scale.
"Again, when a man in violation of the law harms another (otherwise than in retaliation) voluntarily, he acts unjustly, and a voluntary agent is one who knows both the person he is affecting by his action and the instrument he is using; and he who through anger voluntarily stabs himself does this contrary to the right rule of life, and this the law does not allow; therefore he is acting unjustly. But towards whom? Surely towards the state, not towards himself. For he suffers voluntarily, but no one is voluntarily treated unjustly. This is also the reason why the state punishes; a certain loss of civil rights attaches to the man who destroys himself, on the ground that he is treating the state unjustly."
— Aristotle, Nicomachean Ethics Book Ⅴ http://classics.mit.edu/Aristotle/nicomachaen.5.v.html