The resulting feel is a boat that is more calm (sideways) in the gusts.

This is indeed a point that was taken into consideration when drafting the F16 class rules.

This enertia difference is actually quite noticeably.

For a 1-up boat the difference is in the order of 10%-15%

For a 2-up boat the difference is in the order of 20%-25%

That is with respect to increased enertia (=momentary righting moment due to accelleration of the crew upward).

Basically, for the same accelleration (speed) of the crew and luiff hull being lifted up away the watersurface the boat with F16 width will have, roughly speaking, 15-25 % more momentary drive, meaning the boats accelleration forward will be momentary 15-25% more. That is till the point where you sheet out and balance the boat at which point the difference in drive will only become in the order of 2-4% again.

How these differences are translated in to increased speed or covered distance is a different topic. 2%-4% increase in sustained drive for example will only result in about 1-1.75% increased sustained speed for example. Short momentary increased accellerations can quickly be downgraded to only a few meters of gained covered ground because these differences only last for a few seconds at the max (in a race of 2700 seconds !).

Of course a side effect of the wider boat is that this momentary increase in drive will push the bows down more during a gust and make a dive upwind more likely. I have personally never felt this to be an issue on the F16's but there are reports by some owners who have pitched the F16 upwind. On the other hand I wouldn't want to make the F16's wider then they are now, I do believe we are right on a max limit as we are. Some more lengthwise stability (T-foil rudders) on the downwind leg and the F16's will be fully maxed out with respect of what is potentially possible for a boat this size. And in my opinion that is quite alot especially compared to how it does in relation to larger boats.

Wouter