Main Menu vs Navigation Menu Is there a commonly accepted "best practice" for how to use the "Main Menu" vs the "Navigation Menu"? The descriptions in Core add to my confusion:

"The Main menu is used on many sites to show the major sections of the site, often in a top navigation bar."

vs

"The Navigation menu contains links intended for site visitors. Links are added to the Navigation menu automatically by some modules."

I don't intend to start a debate. I'm curious if there's a best practice for how to use these, or is it entirely subjective?
My personal opinion is that this is pretty subjective.

We typically just use the main menu for just top level section links (ie, all links are at the top-level and don't have children), and then will have a menu per site section.  We will also typically have a sub menu for extra header links and extra footer links.  Our theme will take care of displaying the proper menu on pages.

Keep in mind that we also do highly custom themes for large sites, so this scheme may not apply for your needs.