preprocess

Display Suite does not use node-*.tpl.php. This would is be by design. There are three ways i see to bring in custom elements.

Custom fields

Typical usage for custom elements would seem to be creating entire custom 'fields' (as opposed to small variables) which can then be placed by Display Suite-- as shown in the first part of this post:

Remove book entirely, with hook_page_alter()

All, not just most, but all the content on a particular site was set to be posted without showing the by-line or submitted by text. Given this requirement, it makes no sense to have search results show the user that submitted the content, every time. This can be themed away in search-result.tpl.php or it can be removed with a pre-process function as shown below.

You can do this from a module or a theme, where 'example' is the system name of that module or theme: