About gear ratios, in 2014, in a similar situation, Mercedes got their ratios wrong at first.
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They effectively raced withy 7 gears, not 8, for the first races, while Williams had very different gearing. Mercedes had 8th gear way too long, capable of 400 km/h, and rarely used it.
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Come the mid season change, Mercedes essentially copied the initial gear ratio set of Williams.
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In that corrected gear ratio set all the new 1-8th grar range fitted comfortably insode the old 1st-7th gear range, with cushion at both ends.
There is no guarantee that Mercedes has better gearing.
The conclusion bach then was also that gearing wasn't too important to lap time, as they could happily run with 7 or even with 6 gears. Just small optimiztions there.
Dunning asked: Do you know, Kruger? Kruger said: Yes.