Thank you Erica. We're familiar with "fad" here; it was the chevron bit which was mysterious.
I wasn't aware that the pattern had enjoyed special popularity recently, but it most certainly had a spell in the limelight during the medieval period - the chevron is one of the basic heraldic ordinaries by which the field may be divided on a shield. (Ken's much better up on this than me I imagine). In fact, if you drive on the M1 motorway through the Midlands, you will see chevrons painted on the road from time to time: these mark the boundaries of certain ancient feudal demesnes:
and are sometimes supplemented by signs like this:
This one, with chevrons
or (gold) on a field
sable (black) denotes land belonging to the Viscount of Giggleswick, for instance. *
So, as you say, things go in cycles - long ones in some cases!
*I might have been lying about some of that! The basic heraldry is true though.