just to be clear are you wanting to move the Category Description below the products?
So you’re layout would be:
Breadcrumb
Title
Products
Description.
1. Providing the scecond description field in the your Product Category editor.
2. Hooking that description below the Product loop ( which is what a Hook Element would do ).
So unless you already have a way of adding the secondary description then you would need to use the BB Bloomer code.
That code should not make any noticeable difference to the front end performance.