I know you where 'fishing' there 'Griffo' but with bait like that how could I not go for a bite
'taily' oh I understand that the PC well more the PT-6 actually (the airframe is irrelevant really)is very reliable but the whole reason for 2 donks is safety nothing else. The PC is a prime Eg of the fact that you don't need 2 donks to haul around an airframe the size of the old Beech.
Back in the old days when Piper where putting 2gether a 10 seat job (PA31) am sure the main reason for putting two 350 HP donks on the airframe was because they needed twin redundancy, back to that word safety due regs etc. 700 hp would have been achievable with just one large radial thumper up front(using piston donks that is, ugly comes to mind!) but that was never gunna happen. That's all changed these days due the reliability of turbine engines (HP /weight is excellent) but the same underlying reason is still there, safety, whether it's achievable using one or two engines is purely how the risk is mitigated.
It's at the end of the day all about choice & risk. You can have either (2 versus 1) to do the same task/job.
As for two pilot Ops in Aero Med work? Sure that would make it safer again. Two engines, two pilots can't beat that but that concept but it's ALL about cost on that score.
I know which airframe I'd rather be in when an engine goes quiet, no contest there for me
Wmk2