Quoting Pavel Iosad <[log in to unmask]>:

> No, it's definitely short.
> > > But _sa_ and _la_ are kosher even in "proper" Swedish, aren't they?
> >
> > They would be avoided in "serious" writing, if your speaking
> > of the spelling.
> But even SI:s _Svenska utifrån_ book for learners has them. It's pretty
> liberal though, they even write å for att in the later stages.

DN uses _sade_, _lade_, Aftonbladet writes _sa_, _la_, which should be a
decent indication of the stylistic levels involved if you're familiar with
these newspapers. I'd expect the short forms in most fiction.

> > > BTW, is it true that some lects have [stu:g] for _stod_
> > because no other
> > > preterite ends in [d], but plenty of them are in [g] (drog,
> > log etc.)?
> >
> > Can confirm the fact, but not the explanation. Another
> > preterite in /-d/ would be _skred_ "strode".
> Ah yes. Also _vred_? Probably the teacher meant that no other preterite
> *adds* _d_.

Probably, indeed. And _vred_ is right, yes.