Wouldn't it have been more interesting, though, if Sarah Jane and Jo didn't just overload the memory weave but turned the little key weave instead into a weave of the Doctor?

If Jon Pertwee were still alive I'm 100% sure Rusty would have done that, since that is the Doctor that Jo and SJ could collectively remember. Now THAT would have been awesome!

As it is, Matt did an incredible job of looking like Pertwee at a few points in the conversation with Jo on the orange planet.