The torrent of text speculating about something he wrote or drew and what it might mean, is fascinating but in my opinion, so far from the inventor's actual meaning and ultimate intention as to be beyond any likelyhood of revealing the solution. There are clues written within the text but they are ambiguous and hard to make sense of but I’m certain that in the end they will be found to make sense within the laws of physics - they have to, because there cannot be any reason or sense in trying to circumvent them.
In his quote above Bessler says that the two spheres are made of two different materials but they are still spheres. Their differences are not apparent at first sight, but they each have different characteristsics and behave differently under certain circumstances, so at first sight might be misconstrued.
So in my opinion he is saying that FORM or SHAPE is important but two similar shapes may have different characteristics or to put it another way, is, use the SHAPE you see on the paper but don't assume that you understand the way that shape will function and is the way the inventor intended. This is hard to explain. Just because item 'A' on the 'TOYS' page looks like a Jacobs ladder, don't assume that is what it is. Separate the component parts, try merging them to get the intended design but retain the obvious differences.
This digression in DT is there for a reason and I think it is a hint to look at the drawings but don't make any assumptions abut their actions.