As the author seems to admit, an outsider is going to lack so much information (costs, loss leaders, etc), one has to assume any modeling is so inaccurate that it's not worth anything.

So the question remains unanswered, at least for us. For those putting money in, you can be absolutely certain they have a model with sufficient data to answer the question. Since money did go in, even if it's venture, the answer is probably "yes in the immediate, but no over time."