I just don't see the "liberalization" of the Dallas and Houston suburbs. A lot of the "leftward" shift was college educated whites voting for Hillary over Trump. It would certainly explain why some suburban counties like Williamson, Fort Bend, Rockwall, and Denton had that move towards the Democrats. I think it will revert in 2020.
If Trump runs again in 2020, why would it shift? If anything, college educated whites have only gotten more hostile to Trump. In 2020, not only would he lack their support, but he would have suffered some erosion of his actual base, which might even result in lower numbers, not higher. The best way for Republicans to bring these voters back into the fold is to somehow get Trump to just go away by 2020.
I know the traditional view of elections is now up in the air because of 2016. Incumbency is still a good advantage, and if the economy continues to get better then that may be all is necessary for a shift back. Also it's not like the Dems can hit him any harder than in 2016 unless he does/says even more that is stupid, which is likely.
