Rate my fibonacci program

(define (fib n)
  (((lambda (x) (x x))
    (lambda (fhelp)
      (lambda (remaining cpair)
        (if (zero? remaining)
          (cdr cpair)
          ((fhelp fhelp) (sub1 remaining) (cons (cdr cpair) (+ (car cpair) (cdr cpair))))))))
      n (cons 0 1)))

>>22
What are you talking about. The only thing it means is that the thread doesn't get bumped to the top of the list. It has nothing to do with that.