diff --git a/doc/man/man3/notcurses.3.md b/doc/man/man3/notcurses.3.md
index 9a96b055e..8674f3f9e 100644
--- a/doc/man/man3/notcurses.3.md
+++ b/doc/man/man3/notcurses.3.md
@@ -154,7 +154,7 @@ not itself perform any locking.
 * It is **not** safe to add, delete, or reorder ncplanes within a single pile
   from multiple threads.
 
-Only one thread may call **notcurses_getc** or any other input-related thread
+Only one thread may call **notcurses_get(3)** or any other input-related thread
 at a time, but it **is** safe to call for input while another thread renders.
 
 Since multiple threads can concurrently manipulate distinct ncplanes, peak
diff --git a/doc/man/man3/notcurses_plane.3.md b/doc/man/man3/notcurses_plane.3.md
index d4bd0c32b..ec24f07c0 100644
--- a/doc/man/man3/notcurses_plane.3.md
+++ b/doc/man/man3/notcurses_plane.3.md
@@ -396,9 +396,17 @@ When a plane is moved to a different pile (whether new or preexisting), any
 planes which were bound to it are rebound to its previous parent. If the plane
 was a root plane of some pile, any bound planes become root planes. The new
 plane is placed immediately atop its new parent on its new pile's z-axis.
-When `ncplane_reparent_family()` is used, all planes bound to the reparented
+When **ncplane_reparent_family** is used, all planes bound to the reparented
 plane are moved along with it. Their relative z-order is maintained.
 
+## Binding
+
+The planes of a pile make up a directed acyclic forest. Planes bound to
+themselves make up the root planes of the pile. Every plane is either a
+root plane, or bound to some other plane in its pile. A plane and its
+descendants make up a family. When a plane is moved using **ncplane_move_yx**,
+its family is moved along with it.
+
 ## Scrolling
 
 All planes, including the standard plane, are created with scrolling disabled.
@@ -503,7 +511,7 @@ It should not be used in new code.
 # BUGS
 
 **ncplane_at_yx** doesn't yet account for bitmap-based graphics (see
-**notcurses_visual**). Whatever glyph-based contents existed on the plane when
+**notcurses_visual(3)**). Whatever glyph-based contents existed on the plane when
 the bitmap was blitted will continue to be returned.
 
 When the alternate screen is not used (see **notcurses_init(3)**), the contents
diff --git a/include/notcurses/notcurses.h b/include/notcurses/notcurses.h
index 5a1cf7cff..f11731552 100644
--- a/include/notcurses/notcurses.h
+++ b/include/notcurses/notcurses.h
@@ -1244,11 +1244,13 @@ typedef struct ncplane_options {
 // must both be positive. This plane is initially at the top of the z-buffer,
 // as if ncplane_move_top() had been called on it. The void* 'userptr' can be
 // retrieved (and reset) later. A 'name' can be set, used in debugging.
-API ALLOC struct ncplane* ncplane_create(struct ncplane* n, const ncplane_options* nopts);
+API ALLOC struct ncplane* ncplane_create(struct ncplane* n, const ncplane_options* nopts)
+  __attribute__ ((nonnull (1, 2)));
 
 // Same as ncplane_create(), but creates a new pile. The returned plane will
 // be the top, bottom, and root of this new pile.
-API ALLOC struct ncplane* ncpile_create(struct notcurses* nc, const ncplane_options* nopts);
+API ALLOC struct ncplane* ncpile_create(struct notcurses* nc, const ncplane_options* nopts)
+  __attribute__ ((nonnull (1, 2)));
 
 // Suitable for use as a 'resizecb', this will resize the plane to the visual
 // region's size. It is used for the standard plane.
@@ -1296,7 +1298,8 @@ API struct ncplane* ncplane_reparent_family(struct ncplane* n, struct ncplane* n
 // Duplicate an existing ncplane. The new plane will have the same geometry,
 // will duplicate all content, and will start with the same rendering state.
 // The new plane will be immediately above the old one on the z axis, and will
-// be bound to the same parent. Bound planes are *not* duplicated; the new
+// be bound to the same parent (unless 'n' is a root plane, in which case the
+// new plane will be bound to it). Bound planes are *not* duplicated; the new
 // plane is bound to the parent of 'n', but has no bound planes.
 API ALLOC struct ncplane* ncplane_dup(const struct ncplane* n, void* opaque)
   __attribute__ ((nonnull (1)));
diff --git a/src/lib/automaton.c b/src/lib/automaton.c
index 5e209998c..573e0b5bc 100644
--- a/src/lib/automaton.c
+++ b/src/lib/automaton.c
@@ -197,7 +197,6 @@ link_kleene(automaton* a, esctrie* e, unsigned follow){
       e->trie[follow] = esctrie_idx(a, term);
     }else if(e->trie[i] == 0){
       e->trie[i] = esctrie_idx(a, targ);
-      // FIXME travel to the ends and link targ there
     }
   }
   targ->kleene = esctrie_idx(a, targ);
diff --git a/src/lib/notcurses.c b/src/lib/notcurses.c
index d60e09b2d..54fc167a8 100644
--- a/src/lib/notcurses.c
+++ b/src/lib/notcurses.c
@@ -428,7 +428,7 @@ make_ncpile(notcurses* nc, ncplane* n){
 // (as once more is n).
 ncplane* ncplane_new_internal(notcurses* nc, ncplane* n,
                               const ncplane_options* nopts){
-  if(nopts->flags >= (NCPLANE_OPTION_MARGINALIZED << 1u)){
+  if(nopts->flags >= (NCPLANE_OPTION_FIXED << 1u)){
     logwarn("Provided unsupported flags %016jx\n", (uintmax_t)nopts->flags);
   }
   if(nopts->flags & NCPLANE_OPTION_HORALIGNED || nopts->flags & NCPLANE_OPTION_VERALIGNED){
@@ -863,13 +863,16 @@ int ncplane_destroy(ncplane* ncp){
     if( (*ncp->bprev = ncp->bnext) ){
       ncp->bnext->bprev = ncp->bprev;
     }
+  }else if(ncp->bnext){
+    ncp->bnext->bprev = NULL;
   }
   // recursively reparent our children to the plane to which we are bound.
   // this will extract each one from the sibling list.
   struct ncplane* bound = ncp->blist;
   while(bound){
     struct ncplane* tmp = bound->bnext;
-    if(ncplane_reparent_family(bound, ncp->boundto) == NULL){
+    ncplane* bindto = ((ncp == ncp->boundto) ? bound : ncp->boundto);
+    if(ncplane_reparent_family(bound, bindto) == NULL){
       ret = -1;
     }
     bound = tmp;
@@ -2568,19 +2571,21 @@ ncplane* ncplane_reparent(ncplane* n, ncplane* newparent){
 // to be called before unbinding 'n' from old pile.
 static void
 unsplice_zaxis_recursive(ncplane* n){
+  // might already have been unspliced, in which case ->above/->below are NULL
   if(ncplane_pile(n)->top == n){
     ncplane_pile(n)->top = n->below;
-  }else{
+  }else if(n->above){
     n->above->below = n->below;
   }
   if(ncplane_pile(n)->bottom == n){
     ncplane_pile(n)->bottom = n->above;
-  }else{
+  }else if(n->below){
     n->below->above = n->above;
   }
   for(ncplane* child = n->blist ; child ; child = child->bnext){
     unsplice_zaxis_recursive(child);
   }
+  n->below = n->above = NULL;
 }
 
 // unsplice our sprixel from the pile's sprixellist, and then unsplice all
@@ -2616,7 +2621,8 @@ unsplice_sprixels_recursive(ncplane* n, sprixel* prev){
 // recursively splice 'n' and children into the z-axis, above 'n->boundto'.
 // handles 'n' == 'n->boundto'. to be called after binding 'n' into new pile.
 static void
-splice_zaxis_recursive(ncplane* n){
+splice_zaxis_recursive(ncplane* n, ncpile* p){
+  n->pile = p;
   if(n != n->boundto){
     if((n->above = n->boundto->above) == NULL){
       n->pile->top = n;
@@ -2627,7 +2633,7 @@ splice_zaxis_recursive(ncplane* n){
     n->boundto->above = n;
   }
   for(ncplane* child = n->blist ; child ; child = child->bnext){
-    splice_zaxis_recursive(child);
+    splice_zaxis_recursive(child, p);
   }
 }
 
@@ -2646,7 +2652,11 @@ ncplane* ncplane_reparent_family(ncplane* n, ncplane* newparent){
     if( (*n->bprev = n->bnext) ){
       n->bnext->bprev = n->bprev;
     }
+  }else if(n->bnext){
+    n->bnext->bprev = NULL;
   }
+  n->bprev = NULL;
+  n->bnext = NULL;
   // ncplane_notcurses() goes through ncplane_pile(). since we're possibly
   // destroying piles below, get the notcurses reference early on.
   notcurses* nc = ncplane_notcurses(n);
@@ -2658,15 +2668,17 @@ ncplane* ncplane_reparent_family(ncplane* n, ncplane* newparent){
   }
   n->boundto = newparent;
   if(n == n->boundto){ // we're a new root plane
+    logdebug("reparenting new root plane %p\n", n);
+    unsplice_zaxis_recursive(n);
     n->bnext = NULL;
     n->bprev = NULL;
-    splice_zaxis_recursive(n);
     pthread_mutex_lock(&nc->pilelock);
     if(ncplane_pile(n)->top == NULL){ // did we just empty our pile?
       ncpile_destroy(ncplane_pile(n));
     }
     make_ncpile(ncplane_notcurses(n), n);
     pthread_mutex_unlock(&nc->pilelock);
+    splice_zaxis_recursive(n, ncplane_pile(n));
   }else{ // establish ourselves as a sibling of new parent's children
     if( (n->bnext = newparent->blist) ){
       n->bnext->bprev = &n->bnext;
@@ -2675,13 +2687,13 @@ ncplane* ncplane_reparent_family(ncplane* n, ncplane* newparent){
     newparent->blist = n;
     // place it immediately above the new binding plane if crossing piles
     if(n->pile != ncplane_pile(n->boundto)){
-      splice_zaxis_recursive(n);
       pthread_mutex_lock(&nc->pilelock);
       if(ncplane_pile(n)->top == NULL){ // did we just empty our pile?
         ncpile_destroy(ncplane_pile(n));
       }
       n->pile = ncplane_pile(n->boundto);
       pthread_mutex_unlock(&nc->pilelock);
+      splice_zaxis_recursive(n, ncplane_pile(n));
     }
   }
   if(s){ // must be on new plane, with sprixels to donate