The keyword in that quote of yours is "in practice", which means it is not guaranteed that the price will drop after dividends, or drop very significantly.
But yes, you can monitor the stock to see what happens after dividend payouts, just as you can monitor any stock for dips and rises.
Heck, you could also do the reverse if you feel confident in the calculated risk, i.e. buy shares now before the dividend payout (which will be in a while), and then hopefully sell the shares before/on dividend payout day, when/if it climbs to acceptable profit levels.
All in all, as always, since it a stock market, there will always be risk involved, just because the trend happen in the past, not guaranteed to happen again.