Third Party Mandate

Twiglet_1

I have had a third party mandate with the Co-operative Bank for several years for my friend who has difficulty managing his own financial affairs. I am able to to telephone the bank, or go into the branch and discuss (and sort out!) problems he runs into. In fact I generally look after his cash card, so that he has to come and ask me for it before doing anything rash. This has worked well.
He decided (because of the recent negative publicity about the co-op) to move his account to the Nationwide, who, it seems do not offer a third party mandate. The manager who was opening his account called me, and suggested that we should set up a joint account instead. I thought this was very BAD ADVICE, as it would leave me liable for any debt my friend runs up on the account, I was appalled that she had not considered this an issue in the circumstances!
We have decided to go down the route of setting up a power of attorney instead, as my friend is on benefits we are able to get an exemption from the £110 fee for this.
Anyone else had this sort of bad advice from Nationwide?