Thaptw: aorist passive etafhn (epsilon, tau, alpha, phi, eta, nu)
What's the explanation for this? The aspiration seems to have changed place.
Just guessing, I would say that the tau has dissimilated because of the phi. But why the phi? Perhaps it was expecting (or making the analogy with?) another theta aorist passive (luw etc), hence the aspiration?
Sorry if that sounds confused. I hope you get the general idea.