It isn't clear to me what the SCV is advocating with such a salute. I seriously doubt it is pining for a return to slavery, but that is the source of the cause. This dates back to what, 1906? Pre-civil rights era. Slavery was gone, but the 14th and 15th Amendments were being trampled on by Confederates and their sons. So what was the "cause" they were pledging undying devotion to? The usage given in the salute has the characteristics of a dog whistle, even today. Of course, such usages are intentionally vague so that each can see in it...or claim to others that they see in it entirely different things. But if you take the salute at face value, it is an endorsement of the Confederate cause with all the baggage that entails.