I was selected to become an RAF helicopter display pilot. During my work up I was required to fly with a previous one, a fellow, more experienced QHI and my flight commander of the time. He showed me some of the individual manoeuvres he had flown when he displayed and I then took my turn. No problems for either of us. I was then required to fly with him to demonstrate some of the further manoeuvres I intended to fly. Again, no problems for either of us. However, the third stage was combine them into a sequence for approval by higher authority (the Station Commander and then the Air Officer Commanding the Group). Once I made them flow together my flight commander told me he no longer wanted to fly with me because he was beginning to feel unwell!
To get the sequence approved further I had to have it video recorded from the ground and I had to over-dub my own commentary to explain in detail what the more extreme manoeuvres involved. I was cleared to fly it and did so without incident. However, the display was later copied by my successor for a following year but then banned after the (same) helicopter suffered some fairly major tail rotor damage.