True..Its totally random and based on players observation over time we have fixed certain values like around 60 you will get a rare as in kage treasure. I dont think that this has been officially mentioned by OAS anywhere that you would be getting in so many pulls, but we all know from practice. If a meter is put and people are not getting around this value, then people would come around complaining that its a bug , blah blah and blah. People already put such threads in forum, so it will even get worse with introdction of a meter. You cant blame anyone because its just the anticipation for a new ninja that just drives us over the edge. Therefore to avoid such unwanted complications they might not be creating a meter. Just what I think about this meter thing. Personally I think it would be cool to have it since I dont have to keep mental calculations to remember how many seals i have spent.

Lol..I try my best to hold onto scrolls till they reach certain values..but sometimess you just want to know what's in that next draw ten

They should use that law to find out the drop rate of masked man in lucky stars

I think he is unaware of the how much seal scrolls he has spent in summoning treasure and wants a meter to know how close to 2000 he is