Re: "Pager" page-up and -down, why not merge?

[Richard M Stallman <rms@gnu.org>]

    > That in itself is a good thing, but ISTR that the simple
    > implementations of this had bad effects in other cases.

    I'haven't noticed any bad effect (though that means that it is related
    to things I don't use, not that the effects do not exist, of course).

    Care to elaborate which those bad effects are?

I don't remember -- it was something like ten years ago that
I looked at the issue.  It may have involved cases where scrolling
hits the begining or end of the buffer and then you scroll in the
opposite direction.  Or it may have involved cases where you do some
editing then scroll back to where you were.

I think that all simple approaches will cause anomalies, but they will
be different depending on which simple approach.  You may not see them
in usual usage, but they will be there.  You need to think about the
cases where there may be anomalies -- that you do not encounter them
gives no evidence.