After 2 months of waiting for parts (and the scheduled service call) we finally have our Samsung DMR77 dishwasher repaired!
Unfortunately the rack adjust clips seem to be of the same design, which means we can expect the plastic tabs to continue failing. Not impressed!
Here are a couple of pics of the old adjuster clip with broken tabs, and the new adjuster clip in place (where you can clearly see the tabs over the rack tines).
I also mentioned to the tech (a replacement, who was not too familiar with Samsung diswhashers) that wash performance seemed to be deteriorating. He did a quick check and felt that there was not enough water in the bottom of the tub to wash effectively. He suggested trying first a cleaning product, and if there was no improvement, to make a new service call to have the pump checked.
So we will do this, and see what happens! In the meantime I intend to call Samsung customer service about the design of the rack adjuster clips (just for kicks).