Not ironically, I had a pretty hard time convincing some of the fine people(one, specifically) at Intridea that most people felt this way. This was at least a year ago, so I wonder how they feel about it now.
I've always been of the opinion that any kind of coupon box or similar form input ends in exactly the scenario described. I wish this article had some more real data, however, the combined comments of the article and Hacker News seems to elude that the coupon input on your standard checkout flow isn't doing you any favors. I really like the concept of a unique link(possibly creating some kind of session cookie) that enables coupons for people who have arrived through a gateway that dispenses them -- obviously that solution has some cravats, but, not for nothing.
