I myself don't ponder much about the actuarial calculation approach to establish relative MR point values. I not suggesting that it's not worth knowing these relative values, but to me, it's more about the flexibility and serving what ever your particular need is at the moment.
You could in theory garner some 45K more points by paying for the special and have additional points in the MR war chest for another future stay. It all depends upon if you see the $199 special as an earning opportunity, or whether you're ready to burn some points for a nice weekend. Either way you come out ahead.
My philosophy would probably be to pay for the stay and pocket some 55K plus points ( assuming that you're a MR silver with the MR VISA = 10x$199 + 20% bonus for silver + 3:1 on the VISA ).
Have a nice weekend
Barry