Sketch how two black holes approach with pushing plasma tails and merge (1) or split again (2) as Harbig Haro system with "plasma bar"in between. They do not spiral, because they have no mass. Obnly the plasma tails spiral after both black holes are pushed away to become Herbig Haro bowshock black holes or SABHs or GABHs .far away.
Conclusion In LIGO measurements, we do NOT observe the rotation of 2x black holes, but the linear merging of massless black holes in very short time.
