Great while DUB has this advantage at present but almost every major European airport will have US pre-clear in the near future won't they?
Not without significant rebuilding, no. It only really works when you've got a single terminal used for all US-bound traffic. Also, there's not many governments who'd be willing to sign all the required treaties with the US in the first place.
Incheon International announced they wouldn't operating a USPC facility on the grounds of cost, space, usage and the loss of revenue to the airport last month.