Interestingly never really worked out why the 180 degree turn. Most inadvertent IMC is climbing up into it, so what is the point go having to do a 180 degree turn, you are still in it !!!!
I was called out on SAR from Chivenor a good few years ago to search for a missing Cessna that had left Swansea en route to Halfpenny Green or Shobdon in less than perfect weather.
We picked up their 121.5 beacon and homed to it - hover taxing up the side of a wooded hill in the Neath valley in cloud.
Having got to the top, there was slight break in the cloud and in the direction of the beacon signal there was a chap waving to us from the corner of a wood.
We landed on and discovered that he was the pilot and he and his pax were unhurt.
His Cessna was parked at 45 degrees nose down in the middle of the wood.
It turned out he had inadvertently entered cloud in the valley and attempted a 180 turn on instruments.
Fortunately, his IF skills were poor, he climbed (missing the top of the hill) lost speed and stalled the aircraft into the trees which cushioned the impact!
If he had been practised at IF he probably would have speared into the side of the hill at 90 kts.