A colleague (blue with no status) adopted this approach travelling with her disabled daughter. Arriving at T5 with 150 minutes to go, went to a desk to be told the flight (to ZAG) was oversold and they had been offloaded. They were given a £20 pre-paid master card and a re-route through CDG. A delayed LHR - CDG meant she missed the AF connection to ZAG and she was left in limbo with AF saying not their problem (in French) and BA saying talk to AF. This was the last time she booked BA.