Bettwr document the hidden internal sh.c #defines, and which folks
might want to use...
diff --git a/shell/lash.c b/shell/lash.c
index f96720d..bb8a456 100644
--- a/shell/lash.c
+++ b/shell/lash.c
@@ -25,10 +25,18 @@
  *
  */
 
-
-//#define BB_FEATURE_SH_BACKTICKS
-//#define BB_FEATURE_SH_IF_EXPRESSIONS
+//
+//This works pretty well now, and is not on by default.
 #define BB_FEATURE_SH_ENVIRONMENT
+//
+//Backtick support has some problems, use at your own risk!
+//#define BB_FEATURE_SH_BACKTICKS
+//
+//If, then, else, etc. support is really, really broken.  Don't even
+//bother to mess with this yet, since you will not be happy with it.
+//#define BB_FEATURE_SH_IF_EXPRESSIONS
+//
+//For debugging/development on the shell only...
 //#define DEBUG_SHELL