Tue Dec  5 23:18:45 PST 2006  simonpj <at> microsoft.com
  * Improve dependency analysis; makes more dictionaries inlinable

  I recentl changed the scoring system used by dependency analysis for
  recursive bindings, that it used the *form* of the RHS of a binding,
  rather than just its type. In doing so I inadvertently made recursive
  dictionary bindings unravel less well, because I'd missed the case
  of 	c = /\a. C (...) (...)

  This patch fixes the problem.  A good example is the instance for
  Monad (ST s) or Show (ST s a) in GHC.ST.  It's vital for these
  dictionaries to be inlinable.

    M ./compiler/simplCore/OccurAnal.lhs +5