Green and Gold OA: complementary or competitive?

Richard Poynder asks an important question: Open and Shut?: Open Access: Who would you back?:

But as the OA movement has developed an interesting question has arisen: should Green and Gold OA be viewed as concurrent or consecutive activities?

This is not an issue of intellectual curiosity alone: it has important strategic implications for the OA movement. It requires, for instance, that the movement decides whether to treat Green and Gold OA as complementary or competitive activities; and if they are competitive, then where the OA movement should focus its main efforts ...

What do you think?