The differences twixt MR2 & MRA4 fwd of the IFR probe, that would affect IFR, are... NIL.
Yes but John was talking broadly about MR4 AAR trials - trials such as these will consider the whole aero issues of a MR4 airframe in the wake of a tanker to highlight any issues. Issues could stem from any aspect of the revised aero design overall.
If you read his post in this context it does make sense.