I read the points made as being regarding whether engines suffer catastrophic SUDDEN mechanical failure without warning, or not. Pace suggesting they do, regularly, and BPF suggesting it almost never happens WITHOUT warning.
I accept you are speculating and agree the scenario dscribed may well have been the case. However, as I see it, Pace is getting confused and arguing an entirely different point than that being made. Indeed his confusion is apparent when BPF makes his statement re sudden and total failure for Pace to say he has had one only to go on and describe a partial. The pros and cons of each is an argument separate to the point being made.
As I see it BPF is not discussing the benefits of a partial failure versus a complete failure, or vis versa, he is in fact arguing that, since, in his opinion, engines do not suffer catastrophic mechanical failure then the training for such an event is somewhat redundant and the time would be better spent training on the numerous other pilot induced failures that do occur on a regular basis.
Indeed in the scenario you give whereby a partial failure is suffered then the cause of such failure could be pilot induced and therefore further training in this area may have prevented it.
BB