[slime-devel] point jumps around after copious output

After lots of copious output, point tends to jump one screen backwards from the prompt. To reproduce:

* Start SLIME with slime-repl, for example use my slime-setup line:

(slime-setup '(slime-fancy slime-asdf slime-indentation slime-mdot-fu slime-package-fu slime-fancy slime-fontifying-fu slime-sprof))

* Input some command generating copious output, like (require 'foo) where FOO is some system for which fasls don't yet exist.

* Remove focus from the REPL frame, so that the text scrolls down without the window moving.

* When the system is done compiling and a new REPL prompt is drawn, the point will be moved one screen backward from the prompt.

Requested behavior is prompt staying where it is.