I like your rules, Raggytash, you've obviously given this serious thought. If "many" counts as 4, how about "lots/ a lot".I am thinking, for example, of 16 Tons: "a lot of men didnt and a lot of men died". What would you get for that?
   I think you might be being a bit strict making "many" as low as 4. Because if "many" is only 4, then "not many" must be even less. So how would you interpret the famous headline "Small earthquake in Chile: not many killed". Would that imply only 1,2 or 3? These are serious questions that need answers.