Oblaaspop,
Despite I don`t agree with some of your positions , I would like to remember you that an eng.failure on the airbus is considered an abnormal , not an emergency.
When you say that the turkish pilot should have come back mediately and you compare this with the airbus , you are wrong two times.
1.You weren`t sat on that cockpit to judge what he should have done.
2.In the airbus (despite my nickname I´ve flown A-330 as well) , despie on the ECAM you hava LAND ASAP, this is an AMBER LAND ASAP.
So you don`t have urgency to return.Actually , the only one predictable emergency which shows a RED LAND ASAP that could obligate you to return immediately is a fire.
Cheers