for the same reasons as in pool.
I would recommend you set up LP towards one of the big pools.
(after the initial -o pool you add --failover-only -o pooltogetLPfrom -u -p)
That way your miner will get notifications much faster and can drop what he is working on and move on.
Will hopefully reduce the rejected rate and not let your miners chew on a block that has allready been solved ;)
