Change my mind: Tiramisù is better WITHOUT coffee

Tiramisù is a bit of an institution in Italy, no doubt, but as always, my Nonna knew better and she never used coffee. Her recipe was simple. She would use exactly the same ingredients, with the same procedure as the standard Tiramisù but instead of coffee, she would use Vin Santo, a sweet dessert wine. She was right. Therefore I'm right, and everybody else is wrong. That's settled, then. Now let me sit down and brace for inevitable stream of heated comments.