as we know the progression to two engines, two pilots, fully IFR capable aircraft and crews is safer than a light single VFR only machine with a single pilot
Only when those VFR aircraft operate in non-VFR conditions.
The amount of analysis conducted by insurance companies, national aviation authorities and engine producers such as Pratt & Whitney, Detroit Diesel Allison and CFM in the 80's & 90's clearly showed us that single turbine failure rate, as a percentage, was negligible.
Single engine helicopter operations within the proper constraints of their limitations, and with the exception of specialist aerial work operations, remains in the top band of helicopter safety performance (according to statistics) per flying hour overall.