I was also impressed. In general terms, the description of flight at subsonic-jet cruising altitudes is remarkably well-informed by journalistic standards, including the part about coffin corner. Well above average.
17000m is normally on the high side for the tropopause, even in the tropics (was it that high for AF447?). The quoted 25-knot envelope at 10600m (FL350) seems about right, provided you are considering IAS rather than TAS. That doesn't represent most pilots' idea of being close to coffin corner.