I found several threads that discuss how Marriott Gift Checks are used for payment and you still get your points for the stay. I couldn't find any mention of what I experienced this week. I just completed a 10 night stay at a Renaissance and what they did seemed very strange to me.

On the day of departure I dropped off (10) $50 gift checks at the front desk. They delivered the revised bill to my room. Instead of applying $500 as payment, they adjusted the nightly room charge from $169/nt to $119/nt. At first I didn't like this until I noticed they also adjusted the nightly taxes from $21/nt to $14/nt.

So I'm not getting as many points as I would have if they had just applied the payment. But I am saving $70 in taxes. Better deal?

no; you should be credited with MR points on the full $169/night for your 10-nights + your plat bonus................ you do not get MR points on taxes.............

Whether it's a better deal depends on how you value the MR points.

Your $500 spent against the bill at a Renaissance (since it's a Full Service) would be worth 10 points per dollar, or 5000 points. Since you're a Platinum you'd get the 50% bonus, for a total of 7500 points if you take the $500 in checks as payment against the bill.

Taking the $500 as a reduction in rate saves you $70 (in taxes) per your calculations.

I consider MR points to be worth at least a cent each (at least, I don't redeem them unless I get at least that much). At that valuation, the 7500 points are worth $75 or more to me.

So, to me the tax savings is less than the value of the points foregone. Therefore, for me, that would be not a good deal.

I suppose one could opt not to correct the error and accept the savings from reduced taxes, but the fact remains that this is an error in the way the cheques are posted. They are like any other form of payment, and should be posted "below the line", so to speak.