Back in the late 70's/(very) early 80's I seem to recall being told that there'd been some handling problems on the soon to arrive MR2. The little winglet doodads on the tail were, I think, the answer to that issue - at the time the infamous 'somebody' told me that the trials crew had been provided with parachutes while that got sorted out....dunno if there's any truth to that, quite possibly just a silly story at the time.
The "winglet doodads" as you so eloquently put them were installed to counteract the aerodynamic forces of the AAR probe.