tail recursion, again

[forbus@cs.uiuc.edu (Kenneth Forbus)]

   I also just noticed that Winston's Lisp book (3d edition), which purports to
   describe Common Lisp, explicitly says that, "tail recursive procedures are
   handled extremely efficiently by most modern Lisp systems."

Well, he's right. I personally avoid using tail recursion, especially
for classroom code (which is often run on interpreter-only lisps on
micros).  But that's my preference, imposed by non-research
constraints.  I think that optimization is generally an important one.
It's sad when a major vendor decides not to continue to evolve with
the rest.