Everything is pulling on everything else, but in most cases the pull is weak enough that we can pretty much ignore it. What you have done, Caledonian, is akin to telling me the position of three one-gram weights, and then asking me to calculate the motion of Charon based on that.

So close... and yet, so far.

I agree with you that, even if I gave you absolute, complete, and utterly precise data on the three weights, there is no way you could derive the motion of Charon from that.

So: are the three weights evidence of Charon's movement?