I don't know this blog, so I may be missing the point, but it seems like there's not much here: "undo on mobile has never been good. Here's another approach which doesn't work—<i>because I have trained myself to prevent its working</i>." Aside from suggesting preventing the ephemeral 'undo' buttons (it's a nice term!) from being so easily dismissed—which would surely create its own suite of irritations—there doesn't seem to be much that's constructive here; and surely an ephemeral 'undo' as a first iteration is better than no such functionality at all!<p>(That said, as a vimmer, I am used to excellent undo functionality; and I am also frustrated by the failure of undo, and other basic navigation, in most mobile applications, so carefully geared towards the non-proficient user that they grind off all the corners on which a proficient user can hang his or her proficiency.)