Please let me simplify my issue:
My goal: To draw a line (feature) between two points, but without making the line associated to the two points.
It sounds like you want a line feature that isn't associative to other geometry. If so, here is one way to do it:
This will result in a line feature where the end points are associated to locations in space (open the expression editor to see/edit the point expressions).
I have another question, maybe not the same problem but related, I think.
If I create a extrusion from a skecth that is created based on previous geometry and with lines constrained to previous geometry. Is there a way to broke all links quickly? I want now that the extrusion is bases on a fixed plane...
I use that method now, but it is a bit slow and still need to reattach sketch. I was wondering if there is a quickest way to make the whole feature independent of its parents. I dont need to do that very frequently so it is not a big problem anyway.