True enough. My point was that the counter wouldn't have to roll over just because of the limits of the display.
You can display Pi on a calculator and only get so many decimal places, yet you can then subtract 3.14159 from it and retrieve six more decimal places in many cases. The limits of the display does not necessarily limit the underlying calculation (or, in this case, the count).
Only by looking at the circuit or code used could I determine if the thing actually counts modulo 100 (0 through 99 and 'rolling over' dropping anything over 100) or just not displaying the most significant digit.