I won't say I am an expert as I have been searching for errors for only about a year now. I have gone through a large amount of of rolls and so far found three of the 1973-D DDOs.
BTW - there is also listed a 73-D that is missing the F in the designer's initials - I have found a couple of these also.
Normally on the other
DDO dates, I use the leg of the R as the primary point to check, but in the 73-Ds, I have one with a weak strike where it is hard to see the R's doubled leg. But the S's doubling in its bottom curve still shows up well.

How much squash could a Sasquatch squash if a Sasquatch would squash squash?
Download and read: Grading the graders
Costly
TPG ineptitude and No FG
Kennedy halveshttps://ln5.sync.com/dl/7ca91bdd0/w...i3b-rbj9fir2