I will share some Conventional and Unconventional Wisdom for gusty conditions.

Conditions:
The most challenging wind direction at my location is SW direction where wind gets really shifty and gusty because of topography (hills and high rise buildings).
It can drop to 0mph any moment and can gust to 25-30mph in a next (back and forth).
I still use one sail (usually around 11m) for gusts up to 25mph but I am heavy. 200LB (90kg) net, often over 220LB in full gear.

I have a tendency to dive really deep, I will first do the highlights then I can elaborate on any specific item in case there is an interest.
I can also provide some videos that support what I wrote below.

So let’s start:


Sail:

Highly Cambered:
My preference for gusty conditions is to use race sails (highly cambered) and stable in wide wind range. They luff does not collapse in heavy gust, additional “bear wrestling” avoided.

RAF (no cams):
Counterintuitive: For 10.8m Loft Oxygen sail, I use adjustable outhaul to minimum tension in heavy gusts and longer boom setting. Therefore if no gust then boom tension downwards (seat harness) keeps the leach close but when gust hits the upper sail twists, opens and depowers.


Board:
There are several effects that are your enemies in heavy gusts:
1. Wetted area = drag (no matter wide or narrow)
2. Narrow board = board sinks in the chop in lulls instead of staying on top (vs Formula boards, wide boards stay on top and plane the earliest)
3. Fin vs hydrofoil – adding well balanced for speed (slippery) race hydrofoil can enhance early planing while avoiding excessive lift and induced drag
4. Weight of the overall gear: more inertia = less immediate acceleration


The Technique:
Being heavy back footed, and using seat harness with generating MBP (mast base pressure) gives you opportunity to react to the gust and shift weight forward.
I had many “wise guys” who are heavy front footed who tried to convince me that it is a better way, but they like “face planting” or they have never been in conditions where you have 0mph one moment then next 20mph.

Yes Dave, the famous Georges Bay. The wind is probably better in the East but the water surface is like a washing machine with swells coming in all directions. I've tried the Western side but the cliffs at Chimney Heights cause a wind shadow effect that is a real pain.
I do have an update though. Bought a wind foiler and plan to use that in the Westerlies. From what I have seen and read they are better in the gusts and their better upwind performance should help me with getting out away from the wind shadow. Always have my windsurf gear for blasting when it swings back around to the North-East.

The answer of gusty holey conditions is to foil