Earlier this week, a newspaper wrote an article claiming the SPD wants the minority government option. In a first rection, the SPD did NOT deny it. (They did today.)
I think that's a trial balloon, with two goals: (1) to test how the idea is received (it was received with outrage from conservatives), and (2) to make the neoliberal FDP feel queasy and more willing to consider an SPD-Greens-SPD "traffic lights" coalition. *Lunatic*, n. One whose delusions are out of fashion.