I am creating a module that adds an attribute to a product.
If the product has the attribute, on the category page I want to display 'has attribute' below the price and above 'Add to Cart'.
I'm concerned about overriding the template and want to know how best to proceed?
Have you tried referencing product.info.extrahint in your layout xml for the catalog_product_view layout handle and adding your new Block in there? It's an instance of core/text_list and should render Any child passed to it.
The preferred method from my reading is to not override anything, add a new block and provide instructions for the user on how to add that block to their local.xml and call that block in their theme. This way your extension doesn't break anything that might not be compatible on install and gives the user or developer time to review what changes they might need to make so that it is.
