From the article:
"Early in his career, Allen was often his own star, and his distinctive patter—the phobias and neuroses and literary references—worked effortlessly in a way that it does not when it emanates from the mouths of his various surrogates since then."
So true. I miss Woody acting in his movies. The dialogue he writes is funny and natural when it comes out of his mouth, but sounds off coming from, say, Emma Stone.
As for his reputation as an actor's director, I think that stems from him giving almost no direction to his actors. Kenneth Branagh starred in one Woody film, Celebrity, where he essentially did a Woody impression. And after the movie came out (it didn't do well), Branagh was shocked to read Woody Allen criticizing him for the impression, even being baffled by it. Branagh said something like, "Woody was right there on the set. Why didn't he say something to me?"