RE: History for query replace pairs

[Drew Adams]

FWIW, it sounds to me like you are complicating things for no
real gain.  When you are all done fiddling with this, count
the keystrokes needed for a user to take advantage of your
new dream behavior...

Keep it simple.

And just what is the problem that this is trying to solve?
Are you trying to find a way to give users easy access to
previous replacement pairs?  We already have that, no?

If you want to reuse a previous old/new replacement pair,
just use `C-x ESC ESC'.  You have `M-p' or `M-r' to choose
which previous pair to reuse.  And you can edit such a choice.

What's the problem?

---

With a reasonable extension to allow completion on demand
against the minibuffer history (with Icicles you can use `M-o'
to do that, for example), you could also complete-match against
past inputs.  (And yes, it should be on-demand - past inputs
as completion candidates should not just be mixed in with the
current set of completion candidates.)

It might be better to spend a little time to provide such a
past-inputs completion feature than to monkey around adding
keys to maneuver among past input pairs they way you seem to
be doing.  Just a suggestion.