Cloud on the homebuyer's tax credit

Tax Analysts ($) is reporting that the $15,000 tax credit for home buyers included in the stimulus package is in jeopardy. The tax "cost" was originally projected at $18.5 billion, but upon closer examination it has been rescored at $35 billion. No word on what new assumptions led to the revision (end of the recession, perhaps?).

$35 billion is just too darn much for American homeowners to be granted, so some sort of restrictions will be required to "lower the cost." We could also lower the cost by going back to the original assumptions, but that doesn't fit someone's agenda.

Not that I'm expecting to make use of the credit, or even know anyone who is. But I've heard, and I'd like a source on this, that for $800 billion we could actually pay off completely some 95% of all the home mortgages in America. Why isn't that the right way to go?