NCL doesn't have a great track record when it comes to growing markets:
MJV - was served by U2 3X a week, LS came along, pax were given the choice of almost daily flights. U2 left the route, leaving a twice weekly summer only connection with LS. No doubt when there were two airlines on the route the prices would have fallen temporarily, but now? If put money on saying the prices are significantly higher now. A net gain for passengers?
Take MLA. KM and U2 served it for a good few years. LS come along, and history repeats itself with KM pulling the route. A net gain for passengers?
AGP/ALC: the new FR service likely won't grow the market. They will trash yields and chase others off the route. No big loss, until FR then cancel the route and given their previous record of chopping routes at NCL it is very likely. A net gain for passengers?
Let's just hope FR does this before Jet2, easyJet or any of the charters start pulling aircraft out.