When one template or one module initiates an initial link, wikibase could record the ( title <-> entity ) link.
Link exemple ( item = id, guide = new, project = wikisource, namespace = Author )
Later, wikibase could re-use this link from the item to the modules in the page across the call of mw.wikibase.getEntityIdForCurrentPage()
Later also, wikibase could re-use this link in other namespaces, in other projects and in other languages.
If we give to modules the wikibase item.id linked to the title:
- The module writer have not to search it.
- That is made only once for each title.
- The expensive function to find it is no more needed.
- The item.id become a part of the title and is easy to get.