Well, folks; I learned something as a result of this post. After a bit of research, I found this on the Fastenal web site:
The head looks like a star with 8 points. A square bit is used on this drive and it is a called a double because the bit can be inserted two different ways. This gives a second option if the drive is stripped."
So, there really is a double Robertson square drive screw head and it is intended that you use the conventional #2 Robertson square drive bit on it. It appears that there is no "special Torx" bit. Who knew?