I dislike it because it allows reservation of any sites that are within the ' date window' the inquirer requests. While the inquirer may get to choose from a larger pool of available sites for their dates this leaves many open dates in the camp, thus less opportunity for others and income to support the public camp.
A much fairer system would be one that shows only those sites that meet the enquirers specifics.
We have been victims of this policy several times and have witnessed others with less flexible schedules find nothing available for their time frame when making reservations at state parks from Al. to Ca.due to 'cherry picking'.