I would guess that bonus is there to try to get an @example not to
span more than one page.
Right.
On the other hand, it's true enough that the text before an example
usually leads into the example. It seems like this is true of any
environment. Thus perhaps the \penalty-50 should
I was experimenting with adding a page break penalty at the start of
an @example, and some other display environments, because in material
like:
If you want to remove a preinstalled AUC@TeX{} completely before any of
its modes have been used,
@example
(unload-feature 'tex-site)
@end example
