... and you will find some posts by means of the Search function, I am sure. Many say, it does not do any harm, others say - following a most basic law of the universe - "what does not move, cannot break".
I think, when a man like Paul Gerber uses the 7750's stop second hand as a permanent central second in the MIH watch, without stating that the service intervals will be shorter as a result, it should be fine to let it run.
Additionally, you can use the 12 hours counter as a second time zone that way.
Regards,
Marcus