I had a belt that meandered between two lanes because of placement of regular splitters (on a spaceship originally, space constrained). I went to add a second belt in the lower row, using the smart belt drag, and while it successfully put an underground section to build the lower belt, it removed one of the tiles of the pre-existing surface belt. I would expect this tile wouldn't be removed:
By contrast, the belt dragging on the right was all accomplished without removing surface belts.
Log:
Save (new start with /editor):
[2.0.33] Smart Belt Dragging completes underground section but removes existing surface belt
Re: [2.0.33] Smart Belt Dragging completes underground section but removes existing surface belt
As of 2.0.34 it places the underground belt entrance after the splitter where it previously removed the horizontal belt.
Re: [2.0.33] Smart Belt Dragging completes underground section but removes existing surface belt
Thanks Loewchen - I'm not seeing a difference in behavior. I'm on 2.0.34 now: