Simon has the >.

> I may have completely got the wrong end of the
> stick here, but I have the distinct impression
> that some of you who are Icelanders, seem to
> prefer the spellings with Z, even though officially
> abolished, even when writing Modern Icelandic.
> Am I right on this one?

You are correct. Many people who learned to spell
before the change (hotly debated at the time) still
prefer the older standard. Some younger people use
the z too, but that's rather rare. Using the z is
often linked with a couple of other non-standard
methods; such as writing 'eg' instead of 'ég'
and 'hefir' instead of 'hefur'.

I sometimes write in this style.

> Am I right in thinking that when the spelling with
> Z is an option, it sends the message that a D (or T?)
> was once present

Yes. The rule is that when a dental precedes an 's'
the outcome is often written as 'z'.

ð + s > z
d + s > z
t + s > z

Examples:

hand-ski > hanzki (glove)
hund-sa > hunza (ignore)
íslend-skr > íslenzkr (Icelandic)
herð-sla > herzla (hardening)
varð-sla > varzla (custody)
veit-sla > veizla (party)
mart-(i)s > marz (March)

> so maybe HERSLA and ÁHERSLA could, from this
> point of view, better be written with a Z in each case?

Yes.

Kveðja,
Haukur