The table A20 mentioned in BackSeatDriver's earlier post comes from America (and does not apply to us in Aus) and mentions pressure measured to an accuracy of +/- 0.68hPa but reported to a resolution of 0.1hPa. In Australia, pressure is measured to one decimal place and to an accuracy of +/- 0.3hPa. I don't think anyone in Australia measures pressure (for aviation purposes) to more than one decimal place.
I don't think anyone broadcasts metars etc in morse code. I thought it was only the navaids that use morse; is that right?
I agree with Superdimona's thoughts that plain language reporting would be a lot easier and the sooner that happens, the better.