Heavy air: Since opinions on rig set up seem to diverge as wind speeds increase, it is helpful to know the wind and sea state, and also crew weight, for heavy air rig set up. At the Worlds it looked like they had strong, steady winds and big (6 foot) waves. Also, the top teams were probably around the minimum crew weight. In that case, the Galvin set up makes a lot of sense.

In the same conditions with heavier crews, backing off the jib halyard tension a smidge (.5 to 1 inch) would help to power up the sail plan to get through the waves.

An "old school" technique is to back off jib halyard tension a lot (2 to 3 inches) in strong but very puffy wind. The idea is to spill power from the top of the main sail in the puffs.

At some point the sail plan is taking all the wind power it can stand. Above that the sails need to be depowered and there are many techniques that will work and you can have very different set ups boat to boat. Wind, water and weight (3 W's) all need to be considered. Someone should write a book about that!

Rudder stall: Moving crew weight back on the boat can solve the stall problem. I don't know the theory why (rudder "digs in" more?).