TurboSmooth lets you subdivide the geometry while interpolating the angles of new faces at corners and edges. If you apply it to the complete mesh as it is now, Turbosmooth will calculate also the complete mesh. For me, it sounds like you want to maintain the angular/cornered shape of the edges marked with the arrows. If I get it right? than in this case using TurboSmooth you need to chamber the edges marked with the arrows, or manually create multiple closely spaced edges instead of 1. Turbosmooth won´t be able than to "re-calculate" ord even discard your manually created edges, and will keep them as they are (almost cornered). Second approach would be not to use TurboSmooth at all on such critical spots, but instead carefully chambering all edges that should be subdivided and rounded.