A few days ago, I found this comment on an Internet golf forum: Slow down your swing and learn to live with the extra distance you get.
Whenever I'm at the range and I get into a patch of poor ball-striking, the first thing I do is slow down my swing. Most of the time that is all it takes to get back on track. I do the same thing after a couple of bad shots in a row on the course, too.
I hit straight again, and the ball jumps off the clubface and flies out to the full distance I expect from that club, with what seems like no effort at all.
Now I grant you that clubhead speed contributes to distance. You can't chip the ball with a 7-iron as far as you hit it when you swing. But. . .
What is far more important to getting the distance you want, and the accuracy, is square, centered, in-line contact. You might be surprised how far you can hit the ball with just a half swing when all those factors are lined up.
Or let's look at it from the other end. I was at the range with my son a few years ago, trying to show him why he needn't swing so hard. I took out a mid-iron and swung as fast as I could without falling down.
Then I hit another ball using my usual swing speed. The second ball landed less than five yards short of the first ball. All that effort for just a few extra yards and the risk of a poorer shot.
There is just no percentage in swinging hard. You do want to hit hard, but that happens when you have the clubface all lined up at impact. You give yourself a much greater chance of that happening when you swing smoothly, which means slower.
Here's one way to figure that out. When you're on the range, assume that your task it hit one thousand golf balls without taking any big breaks. You would having to be saving your energy on every swing in order to get that done.
On the course, same thing. Assume you're going to play 72 holes today. If you swing for the fences every time, you'll never make it. You need to figure out how relaxed you can be when you swing the club.
Many people think that to be relaxed is to be out of power, lacking in strength. This is not true. What it means is to be using only the necessary amount of muscle power to get the job done. Just like cracking a whip, or casting a fly rod, the center must stay relaxed in order for speed to multiply outwards along the full radius of motion.
I am finding lately that the best way to monitor and keep your tempo under control is by the speed at which you rotate your hips. It should be the same speed going back and swinging through. You absolutely cannot control your tempo with your hands and arms.
Take a lot of swings without a ball, just to build up a sensitivity for the right tempo. When you do put a ball in front of you, be careful, because that by itself makes us swing faster. We don't clobber the ball, we just swing the club.