No, the nipple at the hub end is simply for retaining the spoke, instead of an elbow.
Wheelsmith produced the double threaded spokes in Ti, but couldn't / wouldnt do a "pulstar" type straight pull spoke. Part of the reason for this is when the nipple siezes on a pulstar spoke, it turns the spoke and you can't true the wheel. At least in this instance you can hold the spoke at the other end too if you need to (and with blades you can improvise holding then anyway).
The architecture allows easy lacing of blades too, without having to slot the flanges, although the Ti-stix SS used a regular 28h polished superduper8 on the rear with factory slotted flanges. I have some of these.
"Areo" with the HED rims was quite a driver. At the time DH was more the high speed (mammoth type courses) rather than more modern technical courses. Just look at the size of the big rings on vintage DH bikes. Also the ability to get more tension without risking flange craking.
This is truly good information. The development of the 4,5mm holes as a way to accommodate a bladed spoke without slotting the holes is clever. I am hover still tempted to try to run an upside down straight pull spoke so I can do without nippels on the rim-end. I have found a manufacture of carbon rims that will be able to make a drilling of the rims to accommodate this.... so lets see how this ends up. It s absolutely gonna be a hard job to work on the nippels at the hub side.