Serve and Attack
A discussion I had with Dan Seemiller (5-time U.S. Men's Champion) has always stuck out with me. It was back in 1990-1991, when I spent two summers staying at his house all summer as his assistant coach for all his summer camps. He said that the thing that confused him the most about players was why so many didn't understand what he considered the simple concept that the purpose of the serve was to set up your attack, and that if you aren't attacking off your serve, then something's wrong.
There are two ways of going about this. One way is to develop an attack based on your best serves and the type of returns you get off those serves. For example, early on I developed tricky side-top serves, and so I developed a nice serve & smash. It wasn't until years later that I really learned a good backspin serve & loop game.
The other is to develop serves based on your attack. If you have a good loop, serve short and loop. If you have a good smash or counter-hitting skills, serve more side-top and fast, deep serves.
I finally figured out that the best way to develop serve and attack was to go both ways - learn to attack the type of returns I got off the serves I had developed, and to develop serves that set up my best attack shots. That gives quite an arsenal of serve & attack, and if an opponent can stop one, you can switch to another.
Some might argue that it's better to develop serves based on your best attacking shots, and while there's a good argument for that, it limits your game in that you may find a tricky serve that messes opponents up, but doesn't match your best attacking shots. By using that serve, you'll develop the attacking shot that works with that serve, and you'll have another major weapon.
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