Catch Points & Tie DTM - modify slope creation

If using Catch Points (1) and the selected string is above the DTM surface at the string position, it will only allow a negative slope. (2) Same if the string is below the DTM surface, only allows a positive slope. Whereas users want the flexibility to enter for option 1, enter a ascending positive grade slope and for option 2, enter a descending negative grade - as both options will intersect with the selected DTM surface. Tie DTM has the same scenario, have the ability to enter a opposing slope grade to what is normally expected. Attached is a users request to insert a "positive" ascending fill batter slope.