Well, I found 2 pieces of evidence that the brake and coolant flushes are included in the Maintenance Commitment plan.
The most important is from the MB Warrany Policy and Procedures Manual. Have the dealer look at page 3-33, in chapter 3-26.
"Any authorized Mercedes-Benz Center, passenger or light truck as applicable, in the United States and Puerto Rico will perform the maintenance services specified in the Mercedes-Benz Service Booklet (A and B maintenance services plus additional work required) at no expense to the owner."
To further clarify it, i also found an MB-NET administrative message, dated Nov. 10 1999, in regards to the Maintenance Commitment for model year 2000, it's message #00618, and states, in part:
"Additional work" performed as defined in the client's Service Booklet or the Service (Maintenance) Sheet for Flexible Service System should be included with the appropriate A or B Service as required. The additional work performed should not be submitted as a seperate claim(s) but included with the claim for the respective A or B service."
What that all means is the "additional work" is included, but you can't bring the car in for just the additional work, it has to be done at the same time as an A or B service, just as I said.
This message goes on to outline the coverage of the Maintenance Commitment plan, which is too lengthy to write out here. It lists what is done on an A and B service, and also lists "Additional Work to be performed together with Respective Service"
Every 2 years:
-Replace brake fluid
Every 3 years:
-Replace coolant-water/anticorrosion/antifreeze mixture.
If I had a 2000 or newer Mercedes and paid for a brake or coolant flush (while the car was under warranty, assuming the dealer said "you need a brake or coolant flush, it's time for it"), I think I'd be asking for a refund.