From what I have seen on the race course, the Mossie with kite has a very clear advantage in very light winds (as does an A class upwind). When the wind picks up enough for a T or F18 to double trap, then the advantage is gone and the yardsitcks are realistic. When the breeze increases to the top end of the scale, the yardstick tends to favour the F18 and T more, so the current yardsticks I believe are close overall. If you stuck a kite on an A class, then there will be simular discussions about inaccurate yardsticks when the winds are light.

What I state above is based on the 1 up Mossie. 2 up Mossies are not as brutal in the light stuff as 1 up.