I actually agree LAX - It's not all doom and gloom. But the introduction of TCX to more US routes does raise some questions to which we don't currently know the answers.
From MAN's perspective, it is essential that new services like TCX to JFK and MIA primarily generates new business - those pax that wouldn't otherwise fly the route, or at least not from MAN - rather than simply redistribute existing traffic. There is evidence that some of MAN's TATL services to the US are somewhat fragile - the biggest cut-backs in winter that I can remember, together with reductions in pax numbers in peak summer this year, particularly on ORD and PHL. ATL was significantly down also due to less capacity but LFs stayed reasonable and we have more capacity next summer. I'm led to believe that AA to ORD does not get the consistently high LFs in J class that it once enjoyed. It will be interesting to see how PHL fares in s2015 when there is no CLT. As LAX states, the latter did have some decent loads, including in the small J class cabin.
MAN has affirmed in the recent past that JFK is its most underserved route so if this is the case, then the new TCX flights should be a boost, even allowing for the new DL service.
MIA is a fair bit further south than MCO in Florida but will the new flights affect VS to MCO, or for that matter VS to ATL, or even US to PHL? Being only 2 x weekly, there is a fair chance that any redistribution will be thinly spread anyway against daily flights of the other operators. We wait and see.
However, there is a separate argument about the value of TCX flights against those of legacy carriers. Presumably TCX could be used to connect with Cruise Ships but, unlike AA, they can't realistically expect to gain business going on to South America. Essentially though, TCX is O & D, although of course there is some opportunity of connecting pax at the MAN end with flybe.
More flights to the Caribbean and Canada are definitely welcome.
The objective for MAN surely is to achieve real growth overall and without losing existing important carriers.