This tutorial will show you how to eliminate jaggedness from tight corners in Bob's Track Builder.
As well as looking unpleasant when taking screenshots or watching replays, such glaring anomalies can also be distracting for the driver. Fortunately there is a simple solution:
Add two surfaces, one at the start of the curve(s), and one at the end of the curve(s):
Note the panel length. The number applies to all panels after the selected surface.
Select the surface at the start of the curve(s), and reduce panel length value:
You can see here that a value of 3 has made the corners much smoother. The purpose of the second surface is to set the panel length back to 5 for the rest of the track - we don't want poly-counts to be higher than necessary.
If you had any terrain attached to the track at this location, changing the panel length will cause gaps to appear, and various other distortions. It is best to delete the affected terrain and use BTB's Terrain tool to re-add the terrain using the Click and Drag method.