That appears to me to be an assertion rather than an explanation.
So does that.
Would you like to unveil your agenda, Piscean, or shall we keep dancing around your hidden gripe?
I am open to being convinced that "me" is an indirect object in "Billy asked me for my advice." It had occurred to me that
you might take this very position.
Is it that, when you translate the sentence into German, "me" is in the dative case? Or do you want to argue that the semantic role of "me" is a constant?
Or is your position more avant-garde? Perhaps you want to say that a prepositional phrase can be a direct object! If so, I don't think I can join you.
I accept Quirk
et al.'s view that "me" is an indirect object in a sentence like "Billy asked me to tie my shoes" or "Billy asked me whether it was snowing."
Without reviewing Quirk
et al.'s position, I understand the direct object in those sentences to be in each case the
clause (finite or nonfinite) following "me."
I have not, that I know of, ever encountered the view that a sentence in English can have an indirect object without a direct object.
At the same time, I shall concede that, in a sentence like "He asked me," the object "me" does
feel rather like the "me" in "He asked me a question."
Perhaps in "He asked me" the direct object may be said to be elided.