Is this genuine!

Hi, My minis clutch has gone, I have found a mechanic to repair it but he now says hes found something else wrong with it!! I wonder if anyone could shed any light on this as ive never heard of it. Apparently they have found the '' disposition fork is faulty'' now I may be saying this word wrong but im almost certain that's what they said. I have only had a brand new gear box put in this last year and now the clutch, what is a disposition fork and why would it suddenly go at the same time as the clutch, ive not had any other problems with the car, only with the clutch. Can anyone tell me what this fork is and what it does and why it would go wrong please.