If you always have dessert as part of the meal, at the table, then it's included.
If you only have dessert as a special after-meal course, then it's not included.
I noticed that some of the Sefardim we have invited (in particular, Persians), have no concept of dessert. They don't even like chocolate.

So it's a cultural thing.
We keep it simple - if you've washed, you don't make another blessing. I think - and it's been a few years since I've seen it inside and I'm too lazy to check right now - that it's based on the Mishna Berurah.
Sander, you too - keep it simple. Odds are what you have always done is perfectly fine. It's interesting to hear what other people say and do.
-Kira