blocking for replication returns success with no replication configured

> db.printReplicationInfo()
{
"errmsg" : "local.oplog.$main, or its options, not found in system.namespaces collection (not --master?)"
}

> db.printSlaveReplicationInfo()
local.sources is empty; is this db a --slave?

> coll.insert({})
> db.runCommand(

{ getlasterror: 1, w: 2, wtimeout: 3000 }

)

{ "err" : null, "n" : 0, "ok" : 1 }

The above should fail--it could not possibly have replicated to two servers since there is only one.