You mean, to play from the other side?
Usually, the first move the computer (tactics trainer) makes is a mistake that allows you to use a tactic to gain an advantage if you can find it. From then on, the computer makes the best moves to force you to carry the tactic out accurately to whatever point reinforces the idea.
So you could try to find the computer's best starting move, but then there probably wouldn't be a tactic- you couldn't play 'against' it and it would be like playing out any other game vs. computer.
I hope that clarifies the suggestion idea
In the "Play tactic against computer", is there a way to play AGAINST the recommended tactic? If not, it would be fun to have that feature for those of us who (yes I know!) are silly enough to think that the tactee has not made the best response to the tactor, and would like to try a better defense.