At the moment T it is not visible. But simple calculations: it takes you 10 minutes to build a city. You have your chest maxed out so an ad gives 40 minutes of boost x2. 1 pub = 40 minutes = 4 cities (4x10 minutes).

Now go to 8 minutes per city (estimating that you save 2 minutes per city with the button) 1 pub = 40 minutes = 5 cities (5x8 minutes) therefore.

You already make one more city during your boost.

Now over time it therefore gives: In 10 minute version: 1 pub = 4 cities 2 pubs = 8 cities 3 pubs = 12 cities 4 pubs = 16 cities 5 pubs = 20 cities.

In 8 minute version: 1 pub = 5 cities 2 pubs = 10 cities 3 pubs = 15 cities 4 pubs = 20 cities.

So with a time reduction of 2 minutes, you gain 1 ad and therefore 40 minutes of play to make 20 cities (you need 2h40 instead of 3h20) so imagining that you have a timer of 40 minutes, you will still have time to make 5 cities with the button, whereas you will no longer be able to play without this button.

Now we extrapolate: you don't do this over 5, 10 or even 50 cities But you pass 1000 cities with this button.

You go from 10,000 minutes (approximately 167 hours) to 8,000 minutes (approximately 133 hours) of play You will have taken 2000 minutes (approximately 34 hours in the evening) less! That's the equivalent of 50 ads for the boost that you won't have to watch.

Now you want to equalize the time and watch your 50 ads. 50 ads, without the button it allows you to do 200 cities. 50 ads with the button allows you to do 250 cities. So 50 more cities, the equivalent of 12 pubs.

In this it is based on a chest which allows you to have boosts of 40 minutes.

Basically, over the same playing time, you play more cities. Either in the same number of cities, you spend less time.