This is a microstation/geographic coordinate question. Structual design tool is AECOsim, but that is irrelevant here.
I agree with you that the Helmert transformation should be just an adjustment between 2 sets of coordinates.
But I'm thinking the algorithm Bentley uses to make these geographic adjustments converts things to Lat/Long as a part of the process. (Just a guess) So now my dgn file with the structural information, knows where it is relative to lat/long, but not the civil design coordinate system.
I agree with you that the Helmert transformation should be just an adjustment between 2 sets of coordinates.
But I'm thinking the algorithm Bentley uses to make these geographic adjustments converts things to Lat/Long as a part of the process. (Just a guess) So now my dgn file with the structural information, knows where it is relative to lat/long, but not the civil design coordinate system.
