Why not just Quad?

There has been lots of discussion about what else they will perform besides 
Quadrophenia.  Why does anyone assume there will be more.  I don't think 
it's supposed to be like the Tommy thing in 89.  Has someone read something 
that I haven't.  Given the Hyde Park schedule it seems unlikely that 
anything else will happen, and how much trouble would they go to for just a 
handful of MSG shows.