I totally agree with keeping the message short. Also I have read from several other sources that telling a story is key. But how are you supposed to tell a story in 4 sentences?
You don't have to tell the whole story in the first email. In fact, it's often better to only tell half the story so they get curious to hear the rest.
The title of my article is a decent example: "How I tricked TechCrunch into writing my startup"
Happy to give some feedback based on your individual situation if you like. Email: marc[at]betalist.com
Don't feel the need to be courteous or overly polite. In my pitch I didn't even use complete sentences.
Citing my previous example:
Hi,
My name is X and I'm a founding member of [insert name of startup]. We've developed a new way to [do awesome thing phrased as simply as possible, preferably in the context of other popular startups] and are launching today. We like your publication and wanted to give you first crack at a write-up.
Please message me if you're interested and would like more details.
This reminds me of Fredric Brown, who was able to tell a horror story in two sentenced: "The last man on Earth sat alone in a room. There was a knock on the door..."
So I don't think it should be that hard. I guess the idea is to _not_ tell everything, but let them directly see the potential of developing on some loose ends of that story.
The title of my article is a decent example: "How I tricked TechCrunch into writing my startup"
Happy to give some feedback based on your individual situation if you like. Email: marc[at]betalist.com