On Sat May 28 2005 13:44, Ned Freed wrote:
The X.400 issue is theoretical. I have never seen it happen in practice.
I suspect that the only way to definitively state that reordering has
happened would be to compare "before" and "after" snapshots, and I
suspect that that has been done; RFC 2822 states "they have been known
to be reordered occasionally when transported".
There are plenty of known cases of reordering fields of different types while
not changing the relative ordering of fields of the same type. I believe this
fact is what led to the statement you cite.
Definitively stating that it has never happened -- which is more germane
to the assumption and necessary condition for some schemes -- would
involve "before" and "after" snapshots at each transfer, and I can guarantee
that that has not been done (it's relevant to your comment about the
difficulty of proving a negative).
Of course it is impossible to prove a negative. But experience does count for
something. Of course some folks seem to want to have it both ways - when I say
"I've never seen such and such" they latch on to it like it proves their point,
while simultaneously they choose to ignore the next statement of the form "but
I have seen so and so".