There are several plants that are improved by harvesting often. Many, many years ago a vegetarian exercise instructor friend asked me why red bell peppers were more expensive than green. It is because the longer you leave the fruit on the bush, the less the bush will produce. If you pick them green, you get more bell peppers, so can make more money off of the plant. Like you said, you're tricking the plant. Of course the longer the fruit is on the plant, the more chance there is of disease or fungus or animals having supper before you get to harvest. Hence, red (yellow, orange) bell peppers are more expensive than green. I don't find that keeping other herbs pinched back is as important as it is with basil, but it sure makes a difference there. Now, if someone would tell me how to keep cilantro from bolting .... help!