Earlier quoted context omitted.
No, you are missing the point. There is a value in a future dividend. On the ex-dividend date, the share becomes less valuable because the new holder will not receive a dividend in X days. This X is usually very small, so a share that goes from paying you $5 in two weeks to not paying you has clearly lost value close to $5.
The market cap already reflects the value of all future earnings discounted to the present. The timing of dividend payments is irrelevant. If your argument was true, that a stock's price predictably fell the day after the dividend, investors could simply short the stock and get a guaranteed profit, which is not possible in an efficient market.
False. If I receive cash today I can reinvest it and start earning a return. If I receive cash in a month I have forgone one months reinvestment return.
> investors could simply short the stock and get a guaranteed profit, which is not possible in an efficient market.
False. Well if you are short a stock over ex dividend date then you need to pay the owner of the stock (whomever you borrowed from) 1) the dividend which he has forgone 2) a financing spread equal to a benchmark (e.g. FED Funds + 300 bp's) for the duration you are short.
No offense but you really haven't thought this through very hard.
Also markets are not efficient despite what you read in academia.