",,,socking great canards to control the pitching moment..."
I believe that while the foreplanes are used in starting and stopping manoeuvres they're not sized as conventional control surfaces – compare the FP size to Tornado tailplanes and note the shorter lever arm to the cg. Once the manoeuvre is initiated the foreplanes are used to trim in pitch and enable the flaperons to operate in the middle of their range of movement at all incidences. This way the flaperons shouldn't get too close to saturation (hitting the end stops) and losing pitch control/damping. This also assures plenty of roll control/damping at all incidences. I was once told that for a delta wing, starting the roll is easy, stopping it was the hard part.