Best Practices for adding survey data to an existing surface?

This has been discussed before but without any efficient answer I am asking it again in a slightly different manner.   We survey large irregular property for a local municipality that requires MicroStation.  These sites always require additional topo work to be added after the initial surface is created.  A typical request would involve updating the topo to include areas that have changed due to construction or simply expanding the original topo area.

Each time we add data to the existing surface we must RECREATE THE ENTIRE DTM AND RE-EDIT EVERY SINGLE TRIANGLE THAT WAS EDITED DURING THE ORIGINAL SURFACE CREATION. This process can take days to accomplish depending on the size of the site.  Some sites are over 5 miles long.  

What we need is the ability to add data to a surface without having to re-create it, similar to the the way Civil3d functions.  A 30 minute surface addition in Civil3d can take days in Microstation.  This is extremely frustrating and adds thousands of dollars and tons of wasted time to these projects.  Just yesterday an area was uncovered and it was surveyed.  The area consisted of less then 15 points which needed to be added to the existing surfafce.  Simple, right? Hell no, we had to recreate the DTM and re-edit the triangles.  It took 8 hours to complete what should of taken 15 minutes.

Please do not tell me to 'fix the survey data' or to make every triangle a breakline.. This has nothing to do with bad survey data.  I have been creating surfaces for 25+years and each and every surface needs a detailed review and editing of triangles, basically just flipping faces so the surface is correct.