Coroander - Thank you for the reply and advice. I will continue to work on my underwater photography technique. However, I do encourage everyone who has a OMD or Panny mirrorless camera to do some simple testing of their camera ability to produce sharp images. My tests show that with my 60mm macro (handheld) there is a distinct difference and clarity of the shots in the range of 1/60th to 1/160th shutter speeds (and at f-stops that minimize diffraction) with or without an 1/8sec anti-shock active. Once again, I encourage everyone to do their own testing and come to their own conclusion.
I just wish to point out this situation and a solution, if some photographers are getting less than satisfactory clarity and sharpness on many of their macro shots. It maybe that they nailed the focus and DOF at the time, but the image is soft because of this situation.
Thanks again for your advice - Also I am very grateful for your post on setting up the OMD for underwater shooting. I have incorporated many of your wonderful suggestions in my setup.