I've adopted Coach Dave's catch advice as recommended further by Susanne. It took a few swims to feel normal but now I think I can claim it as mine. At the end of your reach you will feel slight pressure on the back of your hand, let your arm 'flop' in, Daves words I think. At first the timing will be off but if you persist it will pay. The arm simply swings to a position near normal to your travel and you continue it back through the stroke with your rotation. Benefits are: no unnatural rotation of shoulder cuff and extra awareness of reach and rotation. The extra focus on reach makes for an automatic patient hand which makes lots of time for breathing. I love it. I've had to lengthen my open water swims to accomodate the extra ease and performance.
Thanks Dave from the other side of the world, my summer will be extra good with your help.