Bottom line-competing with 16 is more difficult than 15 or less because an entire main stunt group or basket is required. Changes the landscape.
I get the argument of two mans. I'm fine with it being 5 legit two mans. However, your leaving out the 4 vs 3 groups in stunts and baskets.
That's 4 additional people you have to coach up to the same level rather than just stacking 3 groups with your best stunters and 3 tops with 3 people left over to stand.
Clear advantage.