I believe that I bend my wrist when casting and there are no problems at all. You will develop casting styles for different situations and those styles will be the way you cast. I have light rods that I can cast while clamping a book against my body with my elbow. The entire cast is done using wrist and forearm, there are no tailing loops. I can make tight loop casts like this or open loop whichever I want. Listening to casting advice is a good thing to do when you are having difficulties but if you are satisfied with the presentations you are getting then I would work on what you've got and sharpen it from there. Some of the things I have read are like telling me that depending on which shoe I'm wearing when peddling my bike, that shoe will affect my speed. I am quite sure there is a cycling pro who will assure me that this is true.
Are you currently having a problem?