This behaviour doesn't seem normal to me, but maybe I have it setup wrong.
I have some groups that only see documents at a "Release" state. So they don't see the versions that are inwork. On the search form, if I have "Search All Versions" unchecked, these users don't get any hits on a drawing. Checking the box, they do see it.
This is not how I would expect to to work. They should see the latest version they are allowed to see, even if its not the latest version. To them, files that are on an ECO just don't show up in a search anymore until they are released.