rotty.. i know what you are talking about.. but, as a example... my father sued a guy for defamation of character.. the guy was not "malice" with what he was saying but, the accusation was false and could have been "potentially hurtful in regards to income and stature in his community"..(the words by the judge in the verdict).. now, the trainer may not have been trying to hurt clemens (malice) but, what he said to a investigator could most diffinitely be hurtful to clemens in regards to his status (reputation) and could hurt his potential future income..
now i will admit that sueing this guy is like bleeding a turnip.. he probably has nothing to fork over.. and clemens may be better just letting it go as you state.. but, if a guy "defamed" me with no proof but, what he said he saw.. no collaborating witnesses, no video, ect ect.. (his word against mine) i might also look for a way to hurt him..
That is also why I said someone famous or that lives their life in the public eye. It is much more difficult for someone famous to prove the case. Clemens isn't going to lose moneyfrom this, he isn't going to be harmed financially at all and it is going to be almost impossible for him to prove the trainer is lying.