Was the ducking of witches in times past biased against fat women, since the fat ones would float?

Fat women FLOAT??? I don't know what you're talking about, my Aunt Pesca SINKS instantly to the bottom whenever she enters the pool or lake or any other body of water. One time she did a canon ball into the pool at my parents house and we all heard this LOUD thud come from under the ground, it turns out she left something of a CRATER at the bottom of my parents pool and they're STILL patching it up.