Roles no longer restore from backups

Back in the 1.9 days a custom role could be copied from one Moodle site to another through the method described here - http://docs.moodle.org/20/en/Roles_FAQ#How_do_I_copy_a_custom_role_from_one_Moodle_site_to_another - but according to my testing and the discussion at http://moodle.org/mod/forum/discuss.php?d=166572 this classic shonky work-around no longer works.

This may well be a good thing, but the real problem is that the change hasn't been documented anywhere that I can see. If its a bug that this work-around no longer works, then a fix is needed. If the work-around was deliberately stopped from working, then we need to update the documentation to reflect that.

Anyone?