Interesting discussion. Alex, you rightly point to Air AsiaX as an operating long-haul LCC (whether genuinely sucessful or not is unclear) but also don’t forget Jetstar and Scoot so Asia is certainly testing LCC routes that are TA-equivalent regionally, to Australia from Asia and to Hawaii from Australia. These airlines invest in appropriate equipment (A330 etc) with 787s due to Scoot soon so they are minimising operating costs. It will, therefore, be interesting to see how Norwegian fare with their 787s between Norway/ Sweden and the US/ Thailand.
SimonS1, LCCs may have partially seen off BA on European routes but you might also have pointed out that they have done much the same to mainline AF, KLM, LH and SK as well (all of which have had to move to full or partial low-cost models to survive beyond transfer business) while totally killing off Malev. The reality is that no full-service carrier makes money on intra-Europe business so BA is certainly not out on a limb here.