Why Use Pectin vs. Cook Down Method?
There are several reasons.
The first one has to do with the fact that the cook down method takes a lot of time. You will have to cook at a boil for 20 to 30 minutes to evaporate off enough moisture.
This also activates the natural pectin's within the fruit. Unfortunately by doing so you will harm the color, harm the nutrition, and the flavor of the product.
Using pectin allows you to decrease the cook-time significantly; usually at a boil for only a minute or two which gives you better color, a better nutritional product, and better flavor.