Hi Ben,
I rode it south to north because of a fixed starting point, well aware of the wind problem. The high heat of California's central valley causes a more or less permanent summertime low pressure area. Its counter-clockwise circulation creates that wind just about every day.
I did not find it as difficult mentally as Johnsondasw did, and I agree with Valygrl about the value of an early start. The locals told me the wind would return to normal once past Cape Blanco, which did happen for me.
I believe that a lot of the "big deal" depends on your mental set. Know that it will blow, but otherwise be nice temperatures and beautiful scenery. If you start out saying "I'm gonna ride 80 miles today" and don't make it--or struggle to make it--you will indeed be unhappy. If you start out saying "I'm gonna ride seven hours today and take in all the scenery and local color," so what if you only go 50 miles? This is not a race.
For what it's worth, these are ending towns, estimated *average* headwind, and miles for the days I spent in the windy zone in late June 1999:
Rio Dell CA, 9, 63
Trinidad CA, 14, 58
Crescent City CA, 0, 63
Gold Beach OR, 16, 59
Charleston OR, 7, 84
Florence OR, 2, 56
Going into Gold Beach was the worst day. I noted "wind NW@15 at 10:00, 20 at 11:00, 30G40 by noon." Of course the road did not always head straight into the wind, hence my average headwind estimate of 16.
Fred