I must state that nearly all my answers are my own. That means they are possible but not necessarily probable. This is an accepted way of learning.
This is not what I originally wrote. The litvaks would never admit this. They get 'enveloped' in the dancing and say their kovod hatorah is so strong that they just 'couldnt' stop to daven mussaph. Funny its only dancing they cant stop but not learning. That never stopped them davening mussaph.
If you have MZL (motsi zera lavatala) on yom kippur does it mean you will have a bad year and is there anything you can do about it. I am aware the gemoro in yuma at the very end discusses it. But the question really is does it apply today.
Since you stop the answers will have to put it in the question. If someone has NZl on yom kippur rashi says its like raining on sukkot.
If he lives through the year rashi says it proves he was originally a tsaddik. But tshuva would not help if he wasnt.
The pri chodosh lvush say that is impossible. A tsaddik wouldnt be having MZL and certainly not on yom kippur so it must be tshuva helps. The nishmas chayai odom says a tsaddik can have MZL and that was the 'nes' that the kohen godol usually a tsaddik never had.
He says there are three possible reasons for having it. Either he has eaten certain foods. The ones youre not allowed to eat erev yom kippur. He is a rosho which this gemoro is also talking about. He is big tsaddik and the 'chizonim' are having a 'go' at him. (beyond my understanding!). So if he lasts out the year that proves it is the third thing.
They also say that today if someone lasts out the year it doesnt prove he is a tsaddik.
The steipler was asked by a young man who had it and he 'laughed' him off perhaps to placate him. This seems the only place I can put my comments without them being edited.
This most likely needs further explanation. On yom kippur among the five things not allowed is intercourse with a woman. From this gemoro it seems that MZL is also included. In other words if one does MZL on yom kippur aprart from the other issurim he has also transgressed yom kippur.
If it happens to you b'ones rashi says its like raining on sukkot that means hashem is telling you he doesnt need you to keep sukkot or here to keep yom kippur. Plus in this case you will also die within the year. According to rashi there is nothing you can do about it, it is like youre already dead. But you should still do tshuva during the year. The meforshim say he should say the yom kippur davenning daily.(the parts in between the kedusha which most shuls leave out on yom kippur!).