I've not known anyone to have miraculous results from it.
More important seems to be figuring what is causing the tendon to have to work in a sub-optimal and irritating position in the first place (generally in women it's a pronated and internally rotated lower extremity) and correcting that first. Then carefully loading the tendon with repetitive exercise so that it suddenly "wakes up" and realizes it's supposed to heal itself.
Look up the "Alfredson Achilles Protocol." I've seen very good results from that.
"If Americans want to live the American Dream, they should go to Denmark." - Richard Wilkinson