re: $PIP, $DRYS, $OCRX, $PULM discussion

Quick question. I'm sort of new to this. Most books say to hold a stock for one year and one day to pay 15% taxes versus 28% if sold before a year. Does this mean you should hang on for more than a year regardless of performance? What happens if while waiting for that one year and one day mark the stock is in a precipitous decline? What's the most logical strategy to hang on to more of your money? TIA