Serious Goofing Off versus Non-serious Goofing Off
Some players simply do not understand the advantage of SGO (Serious Goofing Off) versus NGO (Non-serious Goofing Off, with apologies to numerous Vietnamese players). In SGO, you are simply goofing off, and besides insulting your opponent, you are not only not helping yourself, you are developing bad habits. However, SGO can actually be valuable. For example, I saw one of our junior players play a lobber by constantly faking a smash and then just patting the ball back. I pulled him aside and said, "If you are going to drop shot his lob, then try to drop it for a winner." In other words, instead of just patting it back, he should go for a side-spin chop block, and try to double-bounce it so the lobber couldn't even get to it, or had to lunge. Another example: If you are going to lob, try to win the lob point with heavy spin (both topspin and sidespin), basically a high loop. Another example: If you are going to just return the serve without attacking it, then, well, do something serious with it - fake one way and go the other, and try to win the point with a "weak" return. Aim to this backhand, and as he's stepping around, go to the forehand and try not to giggle as the server stumbles all over the place trying to get to it.
Who was the all-time greatest SGO champion? Jan-Ove Waldner. You don't develop his touch and control without some serious SGO.
Why can't you serve like this?
Well, why can't you? There really are two types of serves: those whose purpose is to set you up to attack ("third-ball serves"), and those whose purpose is to either win the point outright or set up an easy winner ("surprise serves"). You should develop both.
Highlights of day one of the MDTTC Camp