This is the one thing I haven't seen addressed anywhere. I assume that Apples Hands On phones at the event didn't have any legacy apps installed, and that they weren't letting people install them.
Aaah yes.... the stream! It was truly horrible!! They showed actual screenshots of the unoptimised CNN app:
And they gave an example what the CNN app would look like if it was optimised They said it was "desktop class scaling" and that all text and vector graphics would look as sharp as they would on an optimised app, only larger.