Less is more

I've lost count of the number of times I've been asked "how long should I make my submission?"
For an answer, I'll quote David Ogilvy the eminent ad man who was a renowned copywriter. People often asked him about Copy length - should it be 1 page, a few paragraphs, what's the magic number?
In answer, he said that copy length was irrelevant, "use as many words as it takes to get your message across. Not a word more or less!"
It's the same when you are preparing a response to a tender request (or other submission). Evaluators are driven insane when they are confronted with mountains of paper. Even worse if it is "marketing bumpf"! Concentrate first on deciding what message you are trying to convey - what do you think the potential client's ideal supplier looks like? Once you have decided that, then look at each question you are asked and answer it making sure you reinforce your 'message' with every answer.
Too many words will hide the 'value' you are presenting, and too few will mean you haven't provided enough evidence to justify the message.
Tell me what you're offering; what the advantage is for me; and give me some proof of what you say.