the ex date only matters people dump on record date thinking they will gee the divy but that's not the case, happens all the time. That's why you see the dump next day for the cheapies.
there's an ex-date and a record-date when it comes to divies. which means you need to be owner on record during that time.
If there are large dumps, the share price naturally adjusts to it and people jump right back in after a few days and adjusts back. Then u are faced with a question of buying when the price is low and missing the divvy or getting the divvy and riding it out. I personally found it a headache to try and time those just right.
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