It really is like that. Some people used to count with their fingers differently than we do now. They counted with the thumb on one hand, with each finger beginning (i.e. where the finger is connected to the hand) and each knuckle having a value. In total, with four fingers you get 4x3=12, which is where the expression ‘a dozen’ comes from. The other hand was used to count how many times you did this; strangely enough, with the fingers as we know them. So you could count up to 60.
At least that's how I learnt it at some point. If anyone has more information on this, please let us know!
Incidentally, I find the binary counting method with the fingers more interesting, where you can count up to 1023 with ten fingers.
As long as you film it and put it on the internet, why not!