How to identify schedules placed on sheets?

I have to work on a casework schedule to extract some information about cabinets and the rooms in which they are placed.  If creating a new schedule and performing such task should be pretty straightforward, the team is now working on a half gig (yes GIG) model, and we have one hundred schedules in the browser. This dictates that before we create any new views, we should scavenge the (huge) model for already existing ones.

And here is the problem, because I did find a casework schedule (thanks also to the new search browser feature), but I do not know if it is placed on any sheet, or if it is a working schedule that can be modified without any existing sheet being modified. And no, "go check" is not a viable answer, because the browser also contains hundreds of sheets, grouped in dozen custom groups. So looking for the sheet where a particular schedule might have been placed is simply not feasible.

Organizing the browser to filter out the "not on sheets" parameter works only on regular views, which is bad because Revit thought us that schedules are actually like any other graphic view of the data-set, that is, like floor plans or elevations, they are "sections" cut out of the same database of the 3D model. Yet, they are listed outside the "views" browser item and they seems to have less "rights" than other views.

By the way, Legends seem to have similar limitations, in the sense that they cannot be screened out by "Not on sheet" and if you right click on a legend name, the menu item "Select all instances in view / entire project" is always grayed out. Why can't we at least know how many instances of a particular legend or schedule exist in the project is not clear at this point. This seems to be just an oversight.

If anyone has any idea how to achieve this, please do post a reply. In the meanwhile, not to take any chance, I will have to create a new schedule.