Actually, just found the report online, the BBC whitepaper on the camera.
Indeed what I am seeing with my XL/Nanoflash combo and extra resolution is correct. Roberts states that the camera clearly resolves more resolution due to the pixel offset, but which can also be seen through the HD-SDI port.
http://downloads.bbc.co.uk/rd/pubs/whp/whp-pdf-files/WHP034_ADD25-Canon-XHG1.pdf
Indeed what I am seeing with my XL/Nanoflash combo and extra resolution is correct. Roberts states that the camera clearly resolves more resolution due to the pixel offset, but which can also be seen through the HD-SDI port.
http://downloads.bbc.co.uk/rd/pubs/whp/whp-pdf-files/WHP034_ADD25-Canon-XHG1.pdf