In 1969 I was based at, what was then, Royal Air Force Sharjah. One day we experienced a storm with hailstones that were, genuinely, as big as golf balls. We had a Shackleton sitting on the dispersal and, when we inspected it afterwards, the upper surfaces looked like they had been attacked by a bunch of crazy, ball-pein-hammer-wielding, fitters.
Although it didn't look too good it was deemed, after the ailerons and elevators had been changed, 'fit for flight'.
The crew who flew it said it handled very well (in a Shackleton sort of way) and were convinced that the 'dimples' had, in fact, contributed to enhanced laminar flow.
OK, I'll put my sand-bag away now..............