When I first heard this idea, it sounded plausible. It seems more likely every day.
Hilliary can't win a Presidential election. She's proved that twice.
Biden can't either, but he's got a better chance than Clinton. Biden might be going senile, but he has more personality than a cardboard cutout.
Whenever Clinton speaks, she poisons anything she supports.
So, watch for it.
That's not who sane, rational people would choose. In that, you are correct.
There's a problem with your logic though. Democrats are making the decisions, and right now most Democrats are either hypnotized by visions of free stuff, cowed by political pressures, or simply insane.
Clinton still has money and power. If she wants the Presidency, this is her last chance to get it, I think, even if it is by proxy, being dragged across the finish line by 'Boxer.' (Animal Farm reference.)