Pace
What I was driving at when I said what you quoted was not that you stick blindly to normal procedures when you become aware the nature of your emergency goes outside what your SOPs, briefing and experience to date cover. What I meant was that you hope your experience and training to date and all the experience you have gained along the way will help you identify when you need to step outside the box and then help you take the correct decisions.
Is that any clearer? Probably as mud.
No SOP, briefing or checklist can cover every eventuality. Just the most probable. Anyone supposing you can is rather naive.
The above said I still firmly believe that you should fly what you brief. So with a normal engine failure or fire (if such a thing exists) I would continue above V1.
I'm afraid I'm not that up on the 748 accident although I am aware of it. On the face of it the Captain made the right decision in my view and is to be applauded.
I think the 748s engines are wing mounted aren't they? rather than pod mounted as in most jet aircraft. Will make a difference with a catastrophic failure/fire. An uncontained fore spreading to the wing in a pod mounted engine is much less likely.
I will usually try to visualise an airborne turnback onto reciperical or a cross runway in case I do get an uncontained fire. Top Tip if its an airborne return onto reciperical turn with the wind initially then back into it. This will reduce your risk of flying thru the centerline and needing to increase bank late on in a tightening wind to try to line up.
Also worth checking with the crew if your fire warning goes out as it may be the fire wire has burnt through and the fire is still burning.