From Mental Health Law Online
The donor appointed two attorneys and a replacement attorney. He stated that the replacement should act only if the power given to the original attorneys "is revoked by me" or terminated by death, disclaimer or incapacity. He further stated that the power of his attorneys "shall only come into force only if and when my attorneys have presented medical evidence to the Court and the Court are satisfied that I am or am becoming incapable by reason of mental disorder of managing and administering my property and affairs". On the application of the Public Guardian the condition requiring the attorneys to present medical evidence to the court was severed because, although it was not invalid, it imposed an unreasonable and impractical fetter on the attorneys. The words "is revoked by me" were also severed as being incompatible with section 10(8)(b) of the MCA (revocation of an attorney's appointment is not an event upon which a replacement attorney may act). (OPG summary - LPA case.)
The summary above was taken from the OPG website. Title: Re Saunders (an order of the Senior Judge made on 30 March 2010). Heading: Severance of unreasonable, impractical or uncertain conditions.
No Bailii link - no written judgment