Suddenly running a game at two different resolutions is a very complex process and something that people don't understand how it can work. In a world where PS4 Pro makes developers run their games at 3 different resolutions.
It's amazing, right? Suddenly it's a big issue.
Back in reality and OT, the switch gimmick seems like it will be nice and simple, easy to grasp. I think this should be an easily marketable concept and an appealing one at that. You plug it in, you have HD TV suitable gaming. You unplug it, you can take that exact same* experience on the go. Done.
*
the actual techinical difference between 1080p v 720p(or whatever) being masked by the fact you're now looking at it on a small screen, so drop in resolution and any lower res textures etc are not as noticeable. So for average joe consumer, it's 'the same' experience.