XT is a temporary solution, at best. Everyone understands that. Segregated witness is a better solution in the short run, and in the long run we'll have something else. (lightning network?) So XT does not make much sense, don't think they'll be able to pull it through
Moving transactions off chain is not a solution to scaling the main Bitcoin blockchain, if anything I actually think it is counterproductive over the long run. I have nothing against the lighting network and people should be free to use it if they want. However consciously applying economic policy in a top down fashion in order to arbitrarily "force" higher fees so that the only way to effectively transact in Bitcoin cheaply and quickly is through these type of third parties and off chain solutions is in my opinion wrong and antithetical to the original vision of Bitcoin.