Hrm. The script does complete and give a
Your backported driver modules should be installed now.
message, but it's preceeded by a bunch of:
depmod: ERROR: openat(/lib/modules/3.13.0-24-generic, modules.devname.tmp, 1101, 644): Permission denied
Not sure why it's using resources from the Linux kernel of the machine I'm building on.
EDIT Checked the mod_install directory, the ath drivers from backports seems to have made it in there properly, under the mod_install/lib/modules/3.10.17-xxxx/updates folder.