Our e-commerce site utilizes a CMS and each page is dynamically built based on templates. For example, we have a department-level template, a sub-department level template, and a product template. All of the templates include our navigation module, which is comprised of buttons for each department, with mouse-over dropdowns of the sub-departments.
Google is indexing the navigation module for all of our pages, per Google Webmasters' "Fetch as Googlebot" tool.
Two questions: 1) Does anyone have experience/thoughts on whether the navigation module could "dilute" the optimization of the page? For example, there are 12 Departments, 100+ subdepartments, and not all of them are related. If the bot is reading the links from the navigation bar on a product page, my fear is that the relevance of that product page in a search is undercut by all of the navigation module links.
Any suggestions on how to address this issue (I suppose better site design)?
2) Does the dropdown aspect of the sub-departments (organized in an Unordered List) navigation imply a horizontal site (no hierachy)? Please confirm Y/N.