Rationale problems

[John C Klensin]

--On Saturday, 06 December, 2008 16:14 +0100 Harald Tveit
Alvestrand <harald at alvestrand.no> wrote:

> The other difference is that when a character is UNASSIGNED in
> the user's current Unicode installation, he can use it for
> exactly nothing, so it will not be surprising to him that he
> can't use it in domain names either.
> For instance, he won't be able to see it in an e-mail
> containing an URL that uses the newly assigned character until
> he upgrades his font libraries to support the new character.
> 
> On the other hand, if a character is DISALLOWED on his system,
> he might still see it, be able to type it and use it in other
> contexts. Seeing inconsistent behaviour for whether or not he
> is able to use it in a domain name will be more surprising.
> User astonishment is usually a Bad Thing.

Yes, indeed.

   john