Erik,
Soooo, what this should mean is that if you shoot a 28mm on a M8 and a 35mm on FF and use the appropriate F numbers to get the same DOF, the two will to all intents and pursposes be identical. Just like my 90mm on 5x4 behaves just like a 28 on FF in terms of persepctive etc, only I need to shoot at a much smaller aperture to get front to back sharpness in landscapes compared to a 28mm on FF. On 35mm for a landscape I might shoot at F8/11, but on 5x4 more likely F22/f32 for teh same scene (unless I can use movements).
I am not technically minded so if this contains inaccuracies, please correct me! Hope I am not leading people astray here :O