/* */

stepmania/src/NotesLoaderKSF.cpp

@@ -128,7 +128,13 @@ bool KSFLoader::LoadFromKSFFile( const CString &sPath, Notes &out )
 		notedata.m_iNumTracks = 10;
 		out.m_NotesType = NOTES_TYPE_PUMP_DOUBLE;
 	} else if( sFName.Find("_2") != -1 ) {
-		/* XXX: insert note about pump couples here */
+		/* We never import a COUPLE_1; the _1 side gets imported
+		 * as the SINGLE mode and it gets used as a fallback. This
+		 * way, people can still create separate couples steps for
+		 * the 1p side in Pump (just like you can with any other
+		 * game); we're not stuck with the limitations of KSFs. 
+		 * -glenn
+		 */
 		out.m_NotesType = NOTES_TYPE_PUMP_COUPLE_2;
 	}
 

stepmania/src/Song.cpp

@@ -10,6 +10,19 @@
 -----------------------------------------------------------------------------
 */
 
+/* Couples notes:
+ * Couples is just two sets of notes, paired as a game type, with a fallback
+ * to the normal mode.  This lets us import Pump _2 songs without having to
+ * duplicate the _1 side for couples.  This way, we get to handle couples
+ * the same way in every game.  (Which is nice, because not many people
+ * use couples.)
+ *
+ * This does mean it's impossible to tell (in the current UI) whether a
+ * given song has couples or not; they all show up the same, even if both
+ * sides are using the fallback.  (Except that couples songs tend to have
+ * slightly varying radar values, unless the pattern is just flipped.)
+ * -glenn
+ */
 #include "Notes.h"
 #include "RageUtil.h"
 #include <math.h>	// for fmod