I don't think I saw this mentioned elsewhere in this thread, but another consideration is that, in his position, you have to do all of the sales and marketing yourself. Getting those 6 weeks of paid consulting work may require months of networking at conferences, cold-calling potential clients, making presentations and blogging to keep your public profile as an expert in the field up to date, keeping in touch with industry acquaintances, etc. $30k/week consulting engagements don't just fall on your doorstep, at least not until after you've spent years of work building up a reputation in the industry. Particularly when you live in Japan, and probably have to fly back and forth to the US on spec regularly to meet people, conference, etc.