Oh, I absolutely agree. If they can't clearly see what you're offering they are NOT going to spend their time trying to figure it out. As far as the opening, it wouldn't be a good hook and you want a really strong hook. They'll assume if you can't write a hook, you can't write a novel and go no further.
The order for writing a query letter I see most often is 1. a hook similar to a back cover blurb but no more than 1 or 2 paragraphs, 2. any relevant writing credits, 3. length, genre, title of the book, reference to SASE, and a closing sentence thanking them for their time.
And it should be no more than one page long. The difficulty of writing a good query letter is second only to the difficulty of writing a good novel synopsis. It is enough to make angels weep.
Edit: Here was my own attempt at a query which had at least some success:
When war comes to Wayfare Keep, Tamra has to fight, in every sense, to survive.
Tamra is the Captain of the Guard and nothing can distract her from her duty -- which is why she has joined her forces those of with Sir Cedrian and the army of the city of Madrian to defend their land against invading enemies. When their army is routed and her lover, the ranger Jessup, is lost she is shattered. Even worse lies ahead as the secrets of her past come to light. Each death in battle only makes their enemy stronger, yet in their darkest hour, haunted by loss and with defeat imminent, Tamra and her allies call upon their deepest strengths to survive and triumph.
Warrior's Duty is a 75,000 word fantasy and is my first novel. The completed manuscript is available upon request. Thank you for your generous time, and I look forward to hearing from you.
Cordially,
[This message has been edited by JeanneT (edited September 20, 2007).]