Originally Posted by TravelsLots

Its very simple, they can limit the "NUMBER" of rooms available on certain days. Which means, as long as they offer at least "ONE" room every night of the year, they are OK with the no blackout date system. Totally useless.

Check the FAQ on this here: http://www.marriott.com/rewards/lra-faq.mi

Under the current system you had a better arrangment, Stay Anytime Awards, although with double points, but you still had this option as long as a room was available. Now this option is gone - so hotels can refuse awards stay, other than having just one room per day for such on previously blackout dates, to comply with the new program.

TL