"I can't actually even remember seeing an accident on the NTSB site relating to SE LOC in IMC when flying IFR, which seems surprising."
In the UK we lose 1 or 2 helicopters a year through inadvertent VFR to IMC and subsequent LOC. Almost always VFR single engined aircraft with non instrument rated pilots pushing on through "a little bit of low cloud".
The people who hold a current IR and are flying in an IFR equiped aircraft on an instrument flight plans in big expensive helicopters (mostly equiped with autopilots and lots of systems redundancy) are in a different league as far as managing the risk is concerned.
Personally I quite like being alive and freely abandon my little robbo as soon as the sky gets cloudy for a less scary means of transport. Better to be a warm safe coward...
