What’s the guideline as to when to use Perfekt and Präteritum?
I was always taught that the simplest rule is Präteritum (mostly) for written forms, and Perfekt is most common in spoken language.
But I’ve also come across explanations paying more attention to the context – comparing Präteritum to the French Imparfait (narrative past, little to no influence on current events). That way Perfekt would be mostly used for completed events with present results.
How do you combine those two approaches? Which tense to choose so as not to sound weird in a native context?
For example, would
Ich kaufte einen Computer.
really be the preferred form in writing over the following?
Ich habe einen Computer gekauft.