DOCS-908 correcting mongos connection pooling.

Author: Sam Kleinman

source/faq/sharding.txt

@@ -193,10 +193,12 @@ behavior.
 How many connections does each ``mongos`` need?
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-Typically, :program:`mongos` uses one connection from each client, as
-well as one outgoing connection to each shard, or each member of the
-replica set that backs each shard. If you've enabled the ``slaveOk``
-bit, then the mongos may create two or more connections per replica set.
+Typically, each client maintains as connection to
+:program:`mongos`. :program:`mongos` maintains a connection pool to
+support a single outgoing connection to each shard for. For incoming
+connections that direct read operations to secondaries, the
+:program:`mongos` will also need to maintain connects to each member
+of the replica set that provides the shard.
 
 Why does ``mongos`` hold connections?
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