Aside from aligning it with the summary entry, another reason to say
"never type fallback change" is that if we were to say "to itself", we
should say "never type fall back to itself", grammatically.  But it
seems better here to just use the noun form, so we'll be consistent
with that.

The line wrapping was a bit inconsistent.  Let's just unwrap all the
lines on this page.

On the page for the never type fallback change, we've made a general
copyediting pass.  As part of this, we've also fixed all of the tests
such that they are checked and not simply ignored.

Strangely, some of the longer explanations that had been added to the
ignored tests were causing weird formatting issues in the rendered
output.  The example blocks weren't taking up the full width, and text
was flowing around them.  Making the tests work instead, and removing
these explanations, resolves this issue.