Finding the words
Language is a tool. A necessary tool for any barrister. Choosing the right words carefully is a critical skill.
That does not mean that barristers should just look to use impressive sounding words. It is about the right word for the right audience. Language may differ depending upon whether you are addressing a judge or jury, or on the particular judge. (One judge might like to be addressed as if he were an intellectual, whether he is or isn't, another might value plain speaking). If you are cross examining, then it depends upon the person you are questioning.
In the famous "Lady Chatterley's lover" obscenity trial against Penguin Books in October 1960 the prosecuting barrister showed how an inappropriate use of words can help sink a case below the waterline. He asked the jury, as a means of testing the obscenity case "Is it a book that you would even wish your wife or your servants to read?" . Thus persuading the jury that he had so little contact with reality that they could probably safely ignore what he was saying. Even if that was a totally misleading impression.
There is a legal doctrine called res ipsa loquitur, the thing speaks for itself. What it means is that sometimes an event will happen which, if not explained, will indicate negligence on behalf of the person who, had they taken proper care of that for which they were responsible, could have prevented the event. If you walk into a building and it falls down on top of you then normally, if it was properly maintained, it should not. (Obviously if the owner proved that something else caused the damage like a hurricane, earthquake etc that will be different).
A barrister was once cross examining a witness in a Lancashire county court. He suggested to the witness that this was a clear case of "res ipsa loquitur". "They speak of little else on the streets of Burnley" the judge said acidly. Using the wrong words undermined the point that the lawyer was trying to make.
Sometimes inadvertantly use of words can take that which is intended to be powerful merely ridiculous. I once heard a plea in mitigation, where someone was asking for a lighter sentence. There was some question as to whether the defendant's mental state constituted him a danger to the public. The plea, without any sense of irony, closed as follows: "Imposing such a harsh sentence would be like taking a sledgehammer to crack a nut. ". Though perhaps the most inappropriate use of language in court was of the female United States attorney up against a male attorney. She felt that he was way out of line, she would like to shut him up, and felt she needed to make an objection. As a means of suggesting how strongly she wanted to shut him up she said said that his submissions made her feel like "sitting on his tongue". After an agonising moment of realisation and horror, in some confusion she asked for the remark to be stricken from the record.
A feel for language can also help you expose inconsistencies. I know of one barrister once representing two former public schoolboys who were arrested after a drunken night out. This was in the days before taped interviews. They were alleged to have made full admissions, but the words they allegedly used were plainly working men's words, nothing like the way they spoke. It was not difficult to persuade the court that the alleged confessions could not stand. There was no way they could have spoken those actual words.
Ultimately it is all about context. There is no list of good words and of bad words, it is a question of working out what are the right words, in the right order, for those particular circumstances. Like selecting the right ammunition for the right gun. Necessary if you are to have a chance of hitting the right target.