it happens to me too. Maybe I'm the way too wrong but I think it works like this: There is something like an imediate potential passengers number (not like the total potential that you see when you first open the route), that gets bigger, as much (in some proportion) as the offer. For example, in a route with 1.500 potential passengers, when you start that route, against another airline (assuming that both are using a beech99), you are not competing for 1500 passengers, you're in a competition for something like 23~28 passengers, because otherwise, even in a competition involving 10 airlines for that route, using a beech99, it would not affect your loadfactor at all.
so, I guess it happens when there isnt a strong competition yet, and someone opens the same route as mine, the number of passenger for that route increases, as a whole (looking the competition information, I notice that), and that potential, somehow, increases beyond the capacity of the plane put by the opponent airline, then there are some passenger, say, "left behind", that my airline can take advantage of.
well.. thats all a non empirical thesis. a big guess. don't mind if it is wrong
