Question: can you substitute shredded cheese for grated cheese

Normally, Yes. However, often shredded cheese is made thinner and lighter than grated cheese, therefore it will melt faster. You may also need to pack it down a little if you are putting it in a measuring cup.

I usually use shredded when incorporating in sauces and such because it melts faster. I also use it in pestos because it makes is smoother, the cheese becomes more of the sauce and you not just an ingredient in it.

Now if I want the cheese to melt slower I use grated because it is in bigger pieces. Mac and Cheese does well with grated, so does Pizza usually, especially if it has any other topping that has to be cooked with it too (you don't want the cheese to burn).

It can get confusing though because when you use a micro-grater (that is also a zester), you are getting super fine thin cheese that will melt much quicker, (this is actually the cheese I use in pesto)

I hope this helps and doesn't confuse too much. It does depend on the recipe. I'm noticing the "related recipes" below and they seem to be mostly Mac and Cheese, for those I'd use grated. If you use shredded watch out for burning your cheese, and getting a crust.