Flighted Irons – To “flight” your irons you would set up as normal, but swing with less clubhead speed. Therefore, to add height, you would set up normal but increase clubhead speed. Club speed is the number one way to effect change on trajectory. Of course you can also vary the setup to make the change more extreme, such as changing ball position, hand placement on the club, distance from the ball, width of stance, shoulder tilt, etc, but the primary variable of change remains club speed. The higher the ball goes, the further it goes, until it reaches a point that is too high of course. Most tour pros optimize their distance around 120 feet high, elite amateurs around 100 feet high, while the rest of the world is more around 80 feet high (regardless of club selection). If you are hitting lower than those marks, you are lower than optimum and thus losing distance, so you should work to increase club speed. When you “flight” your irons lower, that lower ball flight means the ball will not fly as far, so extra club will be required. So if you plan to reduce your club speed to lower the ball flight on a windy day, you must account for distance loss.
Knockdown Irons – “Knockdown” shots are fun to execute and really exciting to watch. Within this category you would also have the always appealing stinger. This type of shot requires high club speed but accomplishing a low trajectory through extra forward shaft lean at impact, great ability to stabilize the wrists immediately after impact, and a more held off follow through. This is the most challenging style of trajectory control for the average golfer, as it is difficult to rapidly stabilize the wrists and the clubhead immediately following impact with an abbreviated finish. The “flighted” style of reducing club speed is more recommended in most cases.
Punched Irons – The “punch” is the most extreme in terms of low trajectory as it requires less swing length and less club speed. This is more of a recovery shot if you need to escape trouble. Essentially you are hitting a pitch shot like you would around the greens but with an iron to travel a relatively short distance slightly above ground level. For this shot, you can set up with a narrow stance, close to the ball, and gripped lower on the club like a traditional pitch shot. Whereas the two categories above are useful on windy days, the “punch” is more to get back into position.