Originally Posted by
mahasamatman
The OP was using MR for Membership Rewards.
One poster correctly (for this thread) used "those MR points" to refer to Marriott Rewards, then the next poster ("the OP" you refer to) was who assumed it meant Membership Rewards.
It's Marriott Rewards to SPG that is 3:1 (announced only a couple months ago as one of the first steps in the merger between Marriott and Starwood).