Yes we have established this Mick. And we have also established that you are well aware that Dr Hulsey is expressing movement relative to the CoS.
Is that not the correct way to do this ? Be clear now please.
ADD the net movement of the girder will change depending on the motion of the column. You know this.
And you know that is why i am asking you .
No, really, I have no idea. I just told you that the absolute motion of the column is part of the relative motion of the girder relative to the column. So I'm confused as to why you are asking me about it again.