Also isn't it odd the unpleseant fanatics have so far avoided this thread?
Not really, they can't discuss a serious topic in a civil manner, all they can do is go "0mg 0striches!"
Anyway, to the discussion-
"A red apple is red"
"An apple is a fruit"
"All fruit are red"
"David had a soul in the womb"
"David is a human"
"All humans have souls in the womb"
That's essentially what you're stating. As you say it's not the only possible outcome, but it's not necessarily true.
The only conclusions you can definately prove are that
A) The soul exists
B) Some humans have souls in the womb
The question is whether everyone has a soul in the womb and not just King David.
My opinion is that it doesn't. Since King David is pre-ordained, obviously he is chosen by God to be King before he is born. That is why God gives him a soul. If there was an ordinary person with a soul in the womb, then yes it would definately apply to everyone. But in my opinion David is a special case.
Of course I'm not necessarily right, your opinion is just as valid as mine. Unfortunately the bible is not clear on this (God should have added abortion into the ten commandments

)