[agumonkey]

there are UIs hacking around the idea

sweet expression .. I forgot the name, made the top level forms parens-less

    define fact(n)
      (if ... )

some other hacks include back-shifting any parens by one symbol to turn <fn>(...) into (<fn> ...)

honestly I'm 'astonished' that the sexp debate never dies, no lisper cringes at sexp for more than a week (especially with a structural editing mode)