I'm unsure on terms, so I don't know if I communicated the concept clearly - essentially, it was as you described in the second post. I'm well aware on the relativeness of spatial positions, and the "directions" that appear as a result.

I did some more digging, so let me simplify my idea further: What if the 4 Nomads were used in conjunction with Earth as an astronomical interferometer? We can do fantastic chart work from home, but we can only ascertain so much.

Concerning the Centauri Flyby, I have an idea there. Why not angle the approach so that the probe flys between Proxima and Alpha/Beta until gravitational assistance successfully slows it down to orbital speeds? With constant monitoring and course correction, this would be possible.

Personally, I think we should be sending out deep space telescopes just for this purpose. Imagine what we could discover with synthetic apertures the size of the solar system...