Thanks for the reply.

Yes, you've understood the movements correctly. The starting point with elbow bent at 90 degrees was just intended to make it easier for me to describe. Actually, with the elbow bent at any angle and even the humorous rotated outwards, the elbow is still pulled towards the hand when the wrist makes these movements.

One other fact: If I hold the hand with the fingers gently curved and then while trying to abduct the wrist I flex the thumb and 'first finger' (especially) towards the palm/base of thumb - rather as you would if clenching the fist - then the wrist can abduct much more freely and with a lot less upper arm involvement. In fact, if I squeeze the thumb and first finger together in just the right way, the the upper arm doesn't move at all when I abduct.