The real issue: interopability, and a proposal (Was: Consensus Call on Latin Sharp S and Greek Final Sigma)

[Shawn Steele]

> Please remember that, for many years, existing users needing ö
> (o-umlaut in the German context) used "oe", so carrying this
> argument very far would rapidly turn into an argument against
> any IDNs involving decorated Latin characters.

German's a bit unique in that regard (AFAIK).  As has been pointed out, French and other languages don't have those conventions.  And, the o-umlaut wasn't already being mapped to oe when it was added, it was illegal.  We aren't adding eszett, we're changing the behavior of it.  

> As Patrik points out, the substitutions (both of
> them) are _always_ wrong in Swedish.

I think that the eszett mapping for Swedish would be meaningless, as it is in English.  Not wrong, just pointless.

> I note, fwiw, that many registries and users seem to have
> survived the introduction of "ö".

Because it wasn't legal before.  Eszett is legal.

-Shawn