yup, it's very unlikely to do an ace on the T line. To do some, you have to use the sliced service, and even so, in the higher difficulty levels (ie: Pro and above), you'll do only a few aces.
With a better %, you'll do a bit more aces.
If you want to do a quick try, you can go in the "Training Club", and set your service to whatever you want, set your opponent form (that determines his speed) and difficulty level (that determines his reflexes), and see what happens exactly...
== Mana Games ==
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