As a youngster... I remember my mom and sisters taking part in helping to transcribe stories for a couple of 'pioneer' gals who had been in since... well... for a loooong time. (They both were also 'annointed', too)
I remember that they used a tape recorder to question them, and record their response. It has been a long ago, but if I recall correctly, they had a pre-written set of questions that they had to answer... to make things go faster... and be more uniform (hence the similarity between stories, I suppose).
They transcribed the tapes later, and sent them in to the society. They later appeared as articles in the magazines. I don't recall how much was changed... I think that there was some that got edited and re-written though.
Editors do it all the time.
Regards,
Jim TX