Dump the Queen's English

"To boldly go where no man has gone before" is the most split infinitive of them all, but it has also made the opening sequence of Star Trek probably the most quoted in TV history. Hamlet's unforgettable slings and arrows of outrageous fortune are part of an equally incorrect mixed metaphor.

You don't need good grammar to communicate well. The key to success is to make your message memorable.

"Gillette: the best a man can get". No verb, no sentence and no doubt about the message. Even grammatically correct phrases can be misleading. Menzies Campbell recently referred to the Liberal Democrats as “The Third Party". I assume the other two are Fire and Theft.
You can't abandon grammar entirely. But use it as a platform, not a straight jacket. The best political speeches contain phrasing that is hard to forget (mind you, John F Kennedy's "Ich bien ein Berliner" actually means "I am Jam Doughnut").

Don't worry about grammar, worry about grabbing them. Colourful phrasing stimulates the memory. You want to be remembered for your message. Your message is what you would say if you only had 10 seconds in which to say it. It is the core, the essence of your speech, what you want the audience to remember above all else.

You should spend more time formulating the message than on any other part of your preparation. If you don't have a clear message, you don't have a clear presentation.

In a business speech, the message must clearly encapsulate what your audience needs to know. You don't need Churchillian poetry, but you need clear, concise, plain English. "John Bull Building creates unique homes for families who value space, light and quality".

In politics these days, memorable phrases are commonplace. Even from William Hague: "The powers of this country are being taken away slice by slice with our own Prime Minister wielding the knife."

If you can mix your metaphors so effectively, then your business presentations will become a whole new kettle of ball games.