Ringing Forums

It is covered by a Performance norm in the Framework for Method Ringing.

6C2f) Neither ringers nor conductor(s) used any physical aids to memory during the Performance;

Neither ringers nor conductor(s) used any physical aids to memory during the Performance

Oh dear, all those Stedman ringers shuffling their feet ...

9. Dancing Feet Method
Rule: Mentally label your feet ‘Quick’ and ‘Slow’. When you leave the front, jump on the spot so your other foot is forward. If you are affected by a bob at the back, do another little jump to swap your feet. When you are in 4-5 down, look down at feet and note whether Quick or Slow foot is forward. Go in that way.
Usage: This is more common than you might think, including some experienced ringers.
Pros: Foolproof if you do it properly.
Cons: If you have that bad a memory you may forget which foot is which, and you might forget to do the shuffle. Looks a bit silly.

From An Authoratitive Source, here :-)

using your own body is not a physical aid. If it were then all ringers using their hands to control the rope would be using physical aids.
Reduction ad absurdum!

using your own body is not a physical aid. If it were then all ringers using their hands to control the rope would be using physical aids. — John Harrison

Yes, nice debating point. ...

So, writing the composition on the back of my hand is using my body as a notepad, and that's not a "physical aid to memory", then ... ??

I suspect the real issue is that the Norm isn't as definitive as it might be

If we wanted to argue angels on pin heads then I could point out that the pen used to write it is not part of the body. However from a practical perspective I doubt writing the composition on one's hand would help. The difficult part of calling I find is remembering where you are in the composition while ringing.
But that misses the point. One of the key shifts from the old style Decisions to the current Framework was to recognise that while precision of description is a valid goal, some things - notably the attributes of performances that people value or are interested in - may differ between people or over time. The Framework's role is to enable concise, accurate description of performances, and the idea of a norm: 'something that might reasonably be assumed unless stated otherwise' was intended to cater for that variability without either over complicating most performance reports or outlawing things that didn't fit a rigid mould.
The definition of 'what would reasonably be assumed' is conveniently asymmetric, a bit like the concept of guilt in a court. If there is reasonable doubt then assume it won't.