GUWonder

Yes. We carry passports and other ID around more often because of this. I see more questioning at airports for my SE Europe/SW Asia to EU/Schengen flights than used to be the case two years ago. I also see a few more train schedule delays/cancellations and more temporary passport and customs control checks. Not a show stopper, but there are some disruptions that are worked around in much the same way as when a strike action hits the train schedules.

For those substituting train trips with flights, look at the Avianca promotions currently under way for buying miles and using them for intra-Europe travel. While the added financial expense to go between city centers and airports (in one or both directions) can add up (and will add up in time), sometimes there is a public transit option which can be used for no additional financial expense if the plan already was to rely upon a public transit pass once in the city center.