I still think that you're more focussed on the quantitative than are most other folks here, who are here (at least in part, seemingly) because of the qualitative and therefore exhibit a marked preference for that side of the debate.
I also think that this whole debate at cross-purposes is illustrative of another of chris' observations about traditional marketing theory about "markets" versus the messy reality of engaging with real people. One of the reasons it seems that marketers prefer unidirectional methods is that they don't know how to converse with people! But, if this is so, it is hardly a criticism of conversational engagement.
However, I wasn't rebutting your original post (however much it may have seemed that way - I am far too fond of a good argument so sometimes my mode of expression is unthinkingly aggressive) I was only offering some alternative ways of thinking about the matter. They may or may not be valid, true, or even useful. Just try them on for a bit and see how they fit. If you don't like them, put them back.
I understand the math involved, and I recognise its legitimacy, particularly with regard to scaling issues as you described.
As far as being a book goes, well, I can tell you that very few people have ever offered to pay me for my writings. A more interesting question, or perhaps a question to which the answer might be more interesting, is: "Why is GM-WTWP a successful book?"
(relatively successful anyway, sorry Chris . . . . )
Ask Chris about the Amazon Sales Rankings and their relationship to the EGR letters his alter-ego produces. Ask him about the Sales Ranking of GM even before it was published.
If the number of successful books versus dogs is the be all and end all of quantifying the success of unidirectional methods, then by any objective measure book selling as a unidirecional method is a catastrophe! The ratio of decent product versus crap is overwhelmingly loaded on the crap side of the ledger.
But, of course, anyone (and particularly marketers) are entitled to claim that book publishing is a success because it is profitable. But whether or not marketing can or would want to claim responsibility for its gross inefficiency in terms of selling profitable books is concerned, is another question all together . . . . . . .
Like a knight, on the town
Well it ain't what you dance
It's the way you dance it.
- more from The Spinners