Spearing Britney
On the fleets I've been on, the F/O has always been authorised to autoland, in conditions of Cat 1 or better.
I've seen a very few F/Os autoland, generally when it's their sector and they've had the misfortune to get an aircraft requiring an autoland (in good weather) to upgrade the autoland status back to Cat 3, perhaps after maintenance work.
I've never known a F/O voluntarily elect to do one however.
The general opinion, particularly on the ultra-long haul fleets with augmented crews (where landings for F/Os are not exactly plentiful anyway) would be "Why waste a landing?"
Regards
Bellerophon