I don't have my camera on me right now but you can easily do this. Set focus to SAF (not CAF) in the menu, touch focus to touch (not tracking) and then program the AF button (off hand I am not sure which setting, something with hold, try them out). In video mode, when I press it, it switches to MAF and I see the peaking. It also shows you on the display a button with "MAF on" (but not in the evf). Press it again and you are back to auto focus. This works with and without the hack... Very handy, let the camera pull focus and lock it with the AF button, whether you are rolling or not.