... increasing tolerances just for the sake of not overlapping ... 2 screws and the bigger one has double (percentage-wise) tolerance ...

But the tolerances of the items in question do not change, only their ranges of absolute value. E.g., for 10% (i.e., +/-10%) resistors, a 100 ohm resistor has a range of 90 to 110 ohms, the 82 ohm resistor "below" it ranges over 73.8 - 90.2 ohms, and the 120 ohm resistor "above" it ranges over 108 - 132 ohms. At the other end of that magnitude, 820, 1000 and 1200 ohm 10% resistors range over 738 - 902, 900 - 1100 and 1080 - 1320 ohms respectively.