Hi JJJ,
Polar reversals are a real geological event, I studied them as a part of plate tectonics at Uni when doing a Geology degree.
As the Mid Atlantic ridge widens and releases lava on the ocean floor it cools and up stores a record of the Earths magnetic field for that period in time.
By taking core samples while moving away from the ridge you move into older rocks and the core samples taken have shown that the Earths magnetic field does reverse itself over a period of approx 50,000 years so the whole process is a slow subtle event.
As far as I remember from Uni days they are a sporadic event with the last one occuring a few million years ago.
But I suppose conspiracy theorists have to eat as well.
cheers