diff --git a/r2/r2/lib/db/queries.py b/r2/r2/lib/db/queries.py
index ac3c49aac..f2b3866fe 100755
--- a/r2/r2/lib/db/queries.py
+++ b/r2/r2/lib/db/queries.py
@@ -1355,7 +1355,16 @@ def run_commentstree(qname="commentstree_q", limit=100):
                                         data = True, return_dict = False)
         print 'Processing %r' % (comments,)
 
-        add_comments(comments)
+        # when fastlaning a thread, we may need to have this qproc ignore
+        # messages that were put into the non-fastlane queue and are causing
+        # both to back up. a full recompute of the old thread will fix these
+        # missed messages.
+        links = Link._byID([com.link_id for com in comments], data=True)
+        comments = [com for com in comments
+                    if links[com.link_id].skip_commentstree_q != qname]
+
+        if comments:
+            add_comments(comments)
 
     amqp.handle_items(qname, _run_commentstree, limit = limit)
 
diff --git a/r2/r2/models/link.py b/r2/r2/models/link.py
index 9f467eb0a..9401975b2 100755
--- a/r2/r2/models/link.py
+++ b/r2/r2/models/link.py
@@ -74,6 +74,7 @@ class Link(Thing, Printable):
                      comment_tree_version=1,
                      comment_tree_id=0,
                      contest_mode=False,
+                     skip_commentstree_q="",
                      )
     _essentials = ('sr_id', 'author_id')
     _nsfw = re.compile(r"\bnsfw\b", re.I)