I experimented with various seasoning methods on my carbon-stel woks when I first started getting into Sichuan cuisine.
Salt is a fairly tough abrasive that withstands heat well, and it seems to me that a smoking hot wok gives up even more crap than it does when it's room temperature. It's actually the way that Ming Tsai seasons his woks.
As far as the green onions go, new woks tend to have a metallic and burnt taste to them after seasoning. I find that strong aromatics like green onions and ginger help cleanse those off-flavors and actually impart some of their own flavors to the seasoning. One thing I have noticed with my woks/Lodge gear is that they often impart a slight aroma of the last thing cooked in them to the next dish. Some say along with high heat-toasting of the food, that this is what imparts "Wok Hay" to great eastern foods.
Nick ~ "Egg whites are good for a lot of things; lemon meringue pie, angel food cake, and clogging up radiators." - MacGyver