diff --git a/README.md b/README.md
index b08bde4..229485c 100644
--- a/README.md
+++ b/README.md
@@ -10,6 +10,8 @@ Pick one of the supported directions and **walk continuously forward** for a few
 
 While locked in to a travel direction, players will automatically **swim/climb upward** as necessary to stay afloat and clear simple obstacles such as shores.
 
+Beware that when traveling diagonally, the player may experience "friction" against the edges of nodes that can push them off course, and the course correction may not always be enough to put the player back on the original path; they can end up on a path alongside the original.  You should carefully plan and modify diagonal paths for best reliability.
+
 ### Automatic Turns
 
 When a player is "locked in" to a travel direction, certain structures, when detected, will cause the player to turn automatically and lock in another path 90 or 45 degrees from the previous one.