I'm guessing the optimal tacks will change as the tidal affects of sailing in enclosed waters has an effect. Local knowledge of the effects of the wind and tide sailing in that enclosed space would be more benificial than some machine that cannot project what is going to happen in the immediate future. It is only "making" decisions on what is occurring right now.
The local sailor that utilizes his knowledge will wop your arse all the time. The fact that you can have a wireless wind indicator is neat though.