I can debunk that now Dave.
I just found an old wooden mallet. Typical symmetric head and rectangular-ish haft. I took a marker pen and wrote 1 and 2 on the opposite faces. A and B on the opposite cheeks.
Every time I flip it with the 1 face upwards, I catch it with the 1 face upwards. If I flip it repeatedly starting with the A cheek upwards, it flips to B, A, B, A, B without fail.