The most recent reference I can find to the driver not being able to win the same prize more than once in a season is post # 39336 (Nov. 25, 2013) which I have copy/pasted here for everyone's ease of use. I also cleaned up some of the extra stuff you get when you copy/paste quote boxes and extra format stuff. Anyone can look up the post if they would like to see it in it's original state.
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fastfox400 said
Whats happens when the prize winners have already won the same prize 2 weeks in a row?
zer05ive said
Good catch! Not only can they not with the same prize two week in a row, they can't win the same prize within the same season.
JLBowler said
If they have won the same prize multiple times in one season then everyone that raced in that division on that night is allowed to make one suggestion and the prize winner makes a pick from that list.
zer05ive said
This is spot on. I'll update the results post as soon as possible.
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The ruling was not put into effect here because it was soon after this post determined that the two weeks in question covered two different monthly seasons.