I don’t know about your experiences but I’ve found out in life that most cooks, professionals or amateurs, have a clear preference when it comes to the above question. In many restaurants you can witness the consequences: Quite often, a talented pâtissier decides to open his own shop, just to learn that he can’t really deal with beef and lamb and salty things. Same is true the other way round: Being a great rôtisseur doesn’t mean necessarily that you can handle dessert creams and mousses with similar greatness – so I am convinced that the world of cooking splits up into these two families: the salty guys here, the sweet people there.
In my world, my wife is the pastry chef, and she’s a great one. She’s able to prepare home-made macarons which look (and taste) like coming straight from Pierre Hermé or Ladurée. Her sweet cakes are brilliant, her fruit tarts are incredible, her creams and mousses are just outstanding. But give her a fish and she’s losing confidence. Same with a gigot d’agneau or a beef roast. It’s not that she can’t do it. I’d say: She simply makes part of the sweet faction while I’m on the salty side. I could never ever prepare the berry cake as pictured above; for my wife, it’s not a big deal. Same for the cheese cake below: She’s getting there with ease while I would be completely lost. Social scientists would call it “division of labour”; I call it a win-win-situation.