In a nut shell
You cant pass enough Ishishara Plates to qualify for a JAA unrestricted medical, the lanterns are ok, but they should be testing at high brightness and not at low brightness, third if you cant pass these, then a practice test, ie flight test, light gun signals.
CAA have spend how much on the CAD, and for what...... an arcade test,
by the way, they are saying that there are two types of cad testing a short screening test, and a long 15 minute test, does anyone have any info on this.