Also,
@shouldbeinbed might I be able to get a couple more pictures of your mounting system, with the bag attached, maybe a wider shot without it, etc? (As I notice that we seem to share a similar handlebar stem design)
Cheers!
My apologies, I must have missed this post at the time: photos attached
Its a Cannondale suspension stem with the lockout lever at the top & suspension at the top of the forks, Older pic of the bike in profile, Suspension bit is obscured by the lock.
From the front and above, bag attached
close in to the bracket, bag removed - this bracket front piece slots onto 2 x U shaped arms that hook around the handlebar and are screwed into from the front piece
riders eye view with the bag attached
(optional) bracer piece that stops the bag slipping - I doubt you'd get enough weight into a bag this size for this to be likely, but it is a useful piece on the Mrs' dutch bike with its wicker basket.
It sounds faffy but it is dead easy in the flesh & was a matter of minutes to fit. No worse that the usual hinged bar gripper types.