Gawnsoft said:
> Presumably one does TDD on the domain objects, and some sort of manual
> testing on the interfaces?

Yes.  And we try to keep the GUI components as lightweight as possible. 
Often they become just a matter of wiring this button to that domain
object method.

-- 
-- Jim Weirich     jim / weirichhouse.org    http://onestepback.org
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"Beware of bugs in the above code; I have only proved it correct,
not tried it." -- Donald Knuth (in a memo to Peter van Emde Boas)