Should you change wines during a multiple course?
If you have the opportunity to do multiple wines, absolutely do it. If not, design the meal to go with one wine. Traditionally, multiple course meals start with a white wine and then progress to light reds to bold reds and then to dessert wines.
Wine is an ingredient of course. It is not just a beverage to enjoy with the food. So, you pair the best wine with a given course. This means that you might have a white port with a salad or a red wine with fish. Each course should stand alone as a masterpiece. The food should highlight and make the wine sing.