I already damped the ballast changes by only applying 70% of what the change should have been. I think what exacerbates the swings is that everything in racing is so damn variable. E.g. with the same ballast, I did the middle lap time at Monza, and then won realitively easily at Barcelona.
Next time, I'd definitely only apply a little ballast, like 30% of the calculated amount, to just tighten the field a little.
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