Hi,
I had aquired 24 Omega DPK blanks some years ago and they all were at final size before finish and the joints were .837.
I have also purchased a new custom ordered cue from David in the early 80s and the cue you are showing is much thinner than the Omegas I had so there is a good possibility that he may have built that cue during his short time spent in the Omega Shop.
There is a possibility the a some point they made thinner cues like DPK and later changed the geometry. If you want to know that detailed info contact Mike Bender as he was the talent in that shop as I could be missing something.
JMO,
Rick