How rare?
I have only experience one.
'hardly felt' was not an accurate description, the u/t pilot in the right-hand seat did not know he had landed and thought he was floating. Only the decaying airspeed convinced him that he was not flying.
The instructor said 'you will never do one of those again.'
This was in a Jetstream and a smooth runway also had something to do with it.
Quite unlike a Dan Dare arrival at Inverness. The chap next to me had to see the doc as he suffered injuries to his spine as he had had a previous injury on a Martin Baker let down.