"Duke has produced more than one paper and has spend years on both the Moon and Mars ISRU."

No doubt, which might be why I asked what were you referring to. Btw, I went back through archive and got the URL of the paper I said you might be referring to:
http://www.mines.edu/research/srr/LDEM_Draft4-updated.pdf

"I as well doubt the profitability of building and whole new infrastructure on the Moon to compete with that that exist already on the Earth."

This is nonsense.

"I think Duke and company must have a new and special meaning for the word economic in their papers. And I'm betting they were not reviewed on the economics of the plan but the science only."

You lose your bet.

And actually this paper isn't really advocating that lunar mined water be sold in LEO [at least exclusively in LEO]- because it demonstrates that it probably would not be profitable- in other words within a the relatively short time required for investment capital [less than 10 years] to begin showing a profit even assuming fairly rosy expectations it was losing money. Though there could be ways of making it profitable- such as govt subsidies. For instance, something like a zero tax for space investments might make up the difference. Or govt loans could be solution [not one I recommend though]. And it did mention some factors which might change the operation from being unprofitable to being profitable, one of which was:

"9. The current architecture was built to test a specific commercial market application. Additional markets, including government markets could be included and would raise the net present value of the operation. In particular, sales of propellant on the Moon or in L1 to Moon and Mars human exploration programs could provide significant benefits to those programs and an early human exploration program could choose to develop most of the systems identified in these architectures, allowing a later commercial opportunity to be developed at much lower cost."