There is a hell of a difference between arriving well rested before a 12 hour multi-sector domestic duty and a 14-18 hour LH single sector duty.
You must be well rested before the domestic duty or your performance will suffer.
On the other hand, a lot of pilots sign on to LH duties deliberately under-rested. It's the only way they will manage to get some sleep in the bunk.
Does FRMS consider this little practicality?