Have you ever seen a plane fly backwards? or stalled?
Sailing stalled out (falling in an airplane) with managed projected area (twist or travel) is the key to reducing the excess of wind power you are experiencing. Every notice how slow it is when the crew oversheets the jib, he is depowering/STALLING the sails.
Have you ever seen a plane fly backwards? Sailing stalled out with managed projected area is the key to reducing the excess of wind power you are experiencing.

I addition to getting your weight back, pull your main traveller (& jib) near the center of the boat with minimal twist(sheet in tight), steering ALMOST Dead Down Wind. The closer the mainsail is to the centerline the smaller the projected sail area to the wind reducing wind force and pitchpoling. This sail configuration puts the sail in a STALL, like an airplane falling through the air NEGATING lift.

For steering DDW try using the following (3)three indicators,
that kind of 'check and balance' each other.
First, the bow wind indicator.
Second, pay attention to the feel on helm.
You can maintain a very slight weather to neutral helm with the sails stalled out.
If the helm goes a lee you WILL eventually jibe,
so push the helm away from you to get back to neutral helm.
If the weather helm helm increases pull the stick to get back/close to neutral helm.
Finally, with the jib strapped in (stalled) watch which side the jib FAVORS, as it oscillates
back and forth (how it behaves) out of the corner of your eye, and react accordingly.
This is useful when it is raining so hard you can not see the bridal fly.

Looking behind you, often helps, as you can sheet in before the puff (dark water)
hits you. Its fun watching the other boats go over next to you, as they let OUT their sails.

With the sails stalled the effective shape looks like a big fat wedge whose lee side isn't bending the wind near as much as you'd like, so the lift (component of the force at right angles to the apparent wind) is much less and the drag (component of the force parallel to the apparent wind) is excessive. The combination of the two is smaller and points aft, robbing the boat of the drive.

The above has kept me upright in registered 40kn wind in the "Round the Island" Florida race on a H20.

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So downwind try sheeting in the jib in the puffs to stall out.
To depower more travel in the main to reduce projected sail.
To depower more and stall out reduce twist(sheet in)
and enter the 'Stalled Out Zone'.
(CAUTION sailing stalled in winds under 20nt is SLOW)
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