If they were 100% voluntary -- including RES pilots I think this might be acceptable -- also depends on 2nd and 3rd order effects adding these to the bid package would do. If they're not voluntary, some poor guy on SC will get one of these right at FAR limits and it will absolutely wreck him. Even worse, that flight will be delayed 3 hours by the time it gets to the SC pilot and he'll get 5:15 credit towards guarantee for his trouble.