With some unsuitable passengers, we re-seat them for take off/landing but allow them the extra room during the cruise.
XL ONE:
If you get an in-flight problem and an unscheduled diversion I would have thought the cabin crew have more than enough to do without having to play musical chairs with unsuitable exit-row pax, especially as you are probably Seatbelts On from the occurrence of the problem through to the landing. Are you saying this has made it into SOPs ?
In this country, when in the exit row, I cannot recall the last time it was drawn to my attention.
PAXboy:
Both FlyBe and Easy, at least, do this; more important for low costs with open seating, a crew member standing by the exit during boarding and briefing each arrival in turn. Unfortunately on a recent Easy flight once the cabin was closed up and the crew went to prepare for departure an unsuitable (OK, my judgement) pax moved forward to a vacant exit row aisle seat. Sometimes you can't win.