It’s amazing how long it can take someone to tell you to use fewer words:

Words in prose ought to express the intended meaning; if they attract attention to themselves, it is a fault; in the very best styles you read page after page without noticing the medium. Works of imagination should be written in very plain language; the more purely imaginative they are, the more necessary it is to be plain.
-Samuel Taylor Coleridge

Any one who wishes to become a good writer should endeavour, before he allows himself to be tempted by the more showy qualities, to be direct, simple, brief, vigorous, and lucid.
-H.W. Fowler

The truly brilliant do it better:

Simplicity is the ultimate sophistication.
-Leonardo da Vinci

Men of few words are the best men.
-William Shakespeare

Or with a little irony:

Never use a long word when a diminutive one will do.
William Safire

Or just plain plainerer:

The shorter and the plainer the better.
-Beatrix Potter