[bdunn]

Thanks for your thoughtful comment - the bit about making a guarantee that your product will do X really does make sense when put like that.

Ultimately, I realize a few things 1) relatively few people take up money back guarantee offers and 2) I do want to ensure that people are happy with their purchase. Maybe there's a better way of doing that than ensuring some outcome?

[dchurchv]

"If you aren't completely satisfied with this book I'll return your money, no questions asked" works for me.

No need to guarantee success, just guarantee quality information that you believe when applied correctly will lead to success.