It was no so much the length of the skirt it was more
to do with what the wind was doing to the skirt, and the
contortions the poor girl was going through to maintain
a modicum of decency... which is difficult if your hands
are preoccupied by playing the ukulele.
For me it harked back to that classic scene from the Marilyn
Monroe movie when she inadventantly steps over a hot air vent
and has a tough time keeping her dress done