Tips and advice on the displacment tool (how to make it look realistic)

[Hank hill]

Hi I'm almost finished a map in alpha stage and all I need to know is displacement. I'm making a tunnel a train will go through and the control point will be on top. Easier to explain when its done. Could anyone give advice how to use it properly and make slops and bumps without the ground looking like backwards ice-cream cones sticking out?

 

[FloofCollie]

This article is real handy:
https://tf2maps.net/threads/guide-displacements-basic-construction-part-1.24966/

 

[MegapiemanPHD]

Subdividing a group of displacements can be a good place to start, then edit the result to finish it off.