Updated according to comments

Signed-off-by: Dj Walker-Morgan <[email protected]>

product_docs/docs/pgd/5.6/reference/functions.mdx

@@ -312,11 +312,11 @@ If no LSN is supplied, the current wal_flush_lsn (using the `pg_current_wal_flus
 Supplying a node name parameter tells the function to wait for that node to pass the LSN. 
 If no node name is supplied (by passing NULL), the function waits until all the nodes pass the LSN,
 
-The function operates by polling every 1000 ms for changes from other nodes. Those changes are detected either by looking up the `confirmed_flush_lsn` from the node's replication slot or by connecting to the node directly and querying the results of `pg_replication_origin_progress()`, passing the local node as origin.
+We recommend using this function if you are using [Optimized Topology](../nodes/subscriber_only/optimizing-so) instead of [`bdr.wait_slot_confirm_lsn`](/pgd/5.6/reference/functions#bdrwait_slot_confirm_lsn).
 
-If you are confirming a specific node and the node is concurrently dropped, the wait for that node is ended. If a node is currently down, isn't updating or is simply not able to be connected to, the wait will continue indefinately. To avoid this, set the statement_timeout to the maximum amount of time you are prepared to wait.
+This is because in an Optimized Topology, not all nodes have replication slots, so the function `bdr.wait_slot_confirm_lsn` might not work as expected. `bdr.wait_node_confirm_lsn` is designed to work with nodes that don't have replication slots, using alternative straegies to determine the progress of a node.
 
-We recommend using this function if you are using [Optimized Topology](../nodes/subscriber_only/optimizing-so) instead of [`bdr.wait_slot_confirm_lsn`](/pgd/5.6/reference/functions#bdrwait_slot_confirm_lsn).
+If a node is currently down, isn't updating or is simply not able to be connected to, the wait will continue indefinately. To avoid this, set the statement_timeout to the maximum amount of time you are prepared to wait.
 
 #### Synopsis