Withdraw your libellous statement.
Time to get a hard and fast ruling on this, I think.
The proposal I shall be making is that if, as a requirement of the flight (no matter by whom - ANO, Club or whoever), there is an authorised instuctor on board (i.e. FI or CRI/SPA such as a PFA coach), than that person will be PIC. The other pilot will be Pu/t.
The CAA's wishy-washy statements on this help no-one.