Take first the mote from thine own eye....
We'd moved on from the 'land asap' comments to a discussion concerning levels of risk which, though more restrictive than pure Perf A considerations, would perhaps be more appropriate to continued operation of a 4-engined non-specific airliner with fare-paying passengers on board following the loss of a single power unit.
I consider that 60 min flight time at 2-e speed/alt from en-route alternates (obviously with Wx better than 2-e minima applicable to type) should be the limit.
Thanks, by the way, for all the PMs in agreement with my comments.