While I support the decision to continue the BA flight, there was an interesting article (by SLF) about an engine loss over the Atlantic on Air France (PAR-JFK). Captain's decision was to divert into St. John's NF. AF was unable to move the passengers until the next morning. The writer thanked the Captain over breakfast at the hotel. Certainly, the opposite extreme.
I find it silly to treat 4-engine ops just like ETOPS.
GF