diff --git a/nufxlib-0/Deferred.c b/nufxlib-0/Deferred.c
index 62563f2..ed7bb30 100644
--- a/nufxlib-0/Deferred.c
+++ b/nufxlib-0/Deferred.c
@@ -2511,6 +2511,12 @@ bail:
             *pStatusFlags |= kNuFlushReadOnly;
         }
     }
+
+    /* last-minute sanity check */
+    Assert(pArchive->origRecordSet.numRecords == 0 ||
+        (pArchive->origRecordSet.nuRecordHead != nil &&
+         pArchive->origRecordSet.nuRecordTail != nil));
+
     return err;
 }
 
diff --git a/nufxlib-0/Record.c b/nufxlib-0/Record.c
index fcb31fd..82d8523 100644
--- a/nufxlib-0/Record.c
+++ b/nufxlib-0/Record.c
@@ -349,6 +349,7 @@ Nu_RecordSet_FreeAllRecords(NuArchive* pArchive, NuRecordSet* pRecordSet)
 
     if (!pRecordSet->loaded) {
         Assert(pRecordSet->nuRecordHead == nil);
+        Assert(pRecordSet->nuRecordTail == nil);
         Assert(pRecordSet->numRecords == 0);
         return kNuErrNone;
     }
@@ -545,19 +546,29 @@ Nu_RecordSet_MoveAllRecords(NuArchive* pArchive, NuRecordSet* pDstSet,
         return kNuErrNone;
     #endif
 
-    if (pDstSet->nuRecordHead == nil) {
-        /* empty dst list */
-        pDstSet->nuRecordHead = pSrcSet->nuRecordHead;
-        pDstSet->nuRecordTail = pSrcSet->nuRecordTail;
-        pDstSet->numRecords = pSrcSet->numRecords;
-        pDstSet->loaded = true;
+    /* move records over */
+    if (Nu_RecordSet_GetNumRecords(pSrcSet)) {
+        Assert(pSrcSet->nuRecordHead != nil);
+        Assert(pSrcSet->nuRecordTail != nil);
+        if (pDstSet->nuRecordHead == nil) {
+            /* empty dst list */
+            Assert(pDstSet->nuRecordTail == nil);
+            pDstSet->nuRecordHead = pSrcSet->nuRecordHead;
+            pDstSet->nuRecordTail = pSrcSet->nuRecordTail;
+            pDstSet->numRecords = pSrcSet->numRecords;
+            pDstSet->loaded = true;
+        } else {
+            /* append to dst list */
+            Assert(pDstSet->loaded);
+            Assert(pDstSet->nuRecordTail != nil);
+            pDstSet->nuRecordTail->pNext = pSrcSet->nuRecordHead;
+            pDstSet->nuRecordTail = pSrcSet->nuRecordTail;
+            pDstSet->numRecords += pSrcSet->numRecords;
+        }
     } else {
-        /* append to dst list */
-        Assert(pDstSet->loaded);
-		Assert(pDstSet->nuRecordTail != nil);
-        pDstSet->nuRecordTail->pNext = pSrcSet->nuRecordHead;
-        pDstSet->nuRecordTail = pSrcSet->nuRecordTail;
-        pDstSet->numRecords += pSrcSet->numRecords;
+        /* no records in src set */
+        Assert(pSrcSet->nuRecordHead == nil);
+        Assert(pSrcSet->nuRecordTail == nil);
     }
 
     /* nuke all pointers in original list */