Gold and Ultrarare Duty Officers now properly improve the Success and Critical Success chances on assignments, relative to their quality level.
I see that this does seem to be working correctly, but when I started an assignment and put the one existing gold DOFF in, it did not seem to list any reward bonus in his slot, unlike the others (e.g. +20% for a purple, etc.). As there is no longer a little bar showing your potential crit bonus as there used to be, I won't be able to tell if there is a bonus or not until after the assignment completes.