I agree with tightening the mainhalyard (moves the draft forward and flattens the sail), tightening the cunningham (does the same thing), tightening the outhaul (decreases draft in the lower part of the sailsail), and tensioning the backstay (bends the center of the mast forward flattening the main and tightens the jibstay), but I don't agree with tightening the vang. In strong winds you want the sail to twist off at the top to minimize the heeling force. To do that you ease the vang, depowering the top of the sail and lessening the heeling force. With the vang tight, easing the sheet doesn't have the same effect as when the vang is loose. Easing the sheet with the vang loose lifts the boom and twists the head of the main off, depowering the main sail.
There is a tide in the affairs of men,
Which, taken at the flood, leads on to fortune;
Omitted, all the voyage of their life
Is bound in shallows and in miseries.
Shakespeare, Julius Caesar IV, iii, 217