There's no point. You have the same chance, in the next second, to solve a block that you have already been working on for 13 seconds as one you've been working on for 13 hours. Or 13 days for that matter. The chance of finding a solution within a given time window depends solely on pool hashrate and current difficulty; nothing else. 'History' plays no part.

Now, if something was suspected to be wrong with the server, then that is a different story and a restart can make sense.