Compilation Speed

I have this code:
http://rghost.net/4410616

And it kills SBCL. But if I replace my-lst with

(defmacro my-lst (&rest xs)
  `(list ,@xs))
it compiles much faster.

>>6
>a lot of random and complex code
No. The sequence of lambdas in vecs2 is pretty simple and linear enough, so that with a fast lambda reduction could be reduced to that of vecs1 (meaning no lambdas).