Firstly the amount of Nr decay which will need a very prompt lowering of the lever and a significant flare - if you have speed - if you push the nose down quickly you will decay the Nr further - none of this happens when you have a pre-meditated throttle chop like the one in the video.
I am also reliably informed that the recovered Nr will be lower when there is no assistance from the engine - even at idle it is producing power - and so the RoD is likely to be higher.
The main point is the surprise and disbelief and the likelihood that it will happen at the most inconvenient moment rather than at a height and speed where an easy glide down to the valley is set up prior to the throttle chop.
This post above nails it. Mine wasn't over the mountains.
When it happened I was stunned for a few seconds...I simply didn't think it was real and the NR decay was faster than I remember seeing in training.
If the EOL in the video was real, the voices would be a few octaves higher. Nice video though.