Overall a better analysis than much of what we've seen previously. However the author still makes the mistake of stilting the data in his favor. For example, I've rarely seen a restaurant offer greater than 50% savings. Further, not only does the 40% "regular" rate sound high, it ignores that the Groupon might have produced an extra or quicker visit. The turnaway rate is probably closer to zero given that at-capacity restaurants are unlikely to run these deals. While the redemption rate is not ultimately factored in, it should be pointed out that Groupon has cleverly finessed the issue by making "expired" Groupons worth their paid value.

Finally, we should begin to take into account that deal economics are beginning to change in the merchant's favor. Savings rates are going down (ie 40% savings) and merchants no longer need to pay Groupon 50% of the difference.