Patently untrue. Wrong on steroids.
You are referring to the Shroud of Turin Research Project ("STURP") team investigation in 1978. The primary organizer of that team is not only one of my best friends, but also my co-founder of an organization dedicated to scientific research on the Shroud.
STURP did anything BUT claim it was anything remotely resembling "a Medieval fake". Far from it.
In 1978 I clearly remember as a child the disappointment when they announced the carbon dating found the age of the shroud to be 1200-1300 a.d.. I am not sure if the scientists claimed it was a medieval replica or if it was the people reporting it that took that leap (memory issues) I have however seen on t.v. recently that there is a new theory regarding a flaw in the carbon dating. According to what I heard, they proposed that it was mended using an almost invisible form of “reweaving” that merges new fabric with the old. Unfortunately that was also the area chosen for the carbon dating. My understanding is that the repair includes dyed cotton fabric which is not present in the rest of the shroud. Is this correct, or just another stretch? I figure you are a good person to ask. Also, I understand that there are other datable areas of the shroud that could be used. They said that the shroud was cleaned and all the charred areas were attended to. Some charred pieces were cut away and saved and that these pieces would be extremely good candidates for dating. Please tell me, Is that true? Is it being done?