[chaley]

Try this to see if I understand you correctly.

1. Create a VL using the search you want. A temporary VL (current search) works.
2. Run this template in the template search
   
   Spoiler:

   python:
   def evaluate(book, context):
   	# Set this field to the lookup name of the desired field.
   	field_name = 'authors'
   
   	db = context.db.new_api
   	# Check if we have already computed the necessary data
   	book_ids = context.globals.get('book_ids', None)
   	if book_ids is None:
   		books = {}
   		# all_notes = db.get_all_items_that_have_notes(field_name)
   		for book_id in db.search(query=''): # restrict the search to the current VL
   			item_values = db.field_for(field_name, book_id)
   			if item_values is None:
   				continue
   			if isinstance(item_values, str):
   				item_values = (item_values,)
   			for item_val in item_values:
   				item_id = db.get_item_id(field_name, item_val)
   				if item_val not in books or books[item_val]['count'] > len(item_values):
   					books[item_val] = {'count': len(item_values), 'book_id': book_id}
   		context.globals['book_ids'] = frozenset(bn['book_id'] for bn in books.values())
   
   	# Check if the current book is to be displayed
   	book_ids = context.globals['book_ids']
   	return '1' if book.id in book_ids else ''

It should produce a list of one book per author where the books are limited to those in the VL.

If this is what you want then I will look at ways to eliminate the temporary VL.