Dual currency investments

A reader asked why dual currency investments are risky. I have described this type of risky investments in several postings in my blog. You can read them here:
http://tankinlian.blogspot.com/search?q=dual+currency+

There is a chapter in my book, Practical Guide on Financial Planning, that explains the the risk of various tyoes of structured products, including dual currency investments, and of unregulated products, such as land banking, ponzi schemes and other scams.