Well maybe it's time rules aren't made for just one manufacturer. Couple years back 5 cell mod was brought up to 1425g instead of 1400 just because one manufacturer couldn't make a car to a similar weight as all the other makes.
And to be perfectly clear, 1350g makes sense as the rules were for 1500g for nimh and nicads, which are 150g heavier than the heaviest legal lipos of the moment.