nightcreacher said "its a safety issue.when you have run 690 miles,including your dead head,and your getting tired.you have an accident,not your fault,but the officer sees you have driven almost 700 miles,the last 11 hours,what do you think is going to happen?"
The Flex in Flex 700 should be flexible. If I have 48 hours off I can easily run a 800-900 run. I've done it many times doing a run then deadheading back toward home. It should be a choice, not everybody wants to run 700+ runs. I had days where 500 miles was to many. I have gotten up 3am to run 100 mi to pu then ran 200 for the run, and gotten an offer for another run picking up right away. Fedex CC follows the 700 mi limit at their convenience
Drivers should have the same convenience with common sense rules. Ex: If a driver has a full 48 hours off duty a 800 or even 900 mile run can be offered. (Panther drivers can run 900 miles) then they have 500 mile rule the if they don't get a certain amount of time off)