Never. Like I said, a change like this in the deduction would probably depress sales of expensive properties, or at least reduce the size of mortgages.
But my opinion remains the same that this particular proposal will not affect most Americans, and those Americans whom it will effect will have a variety of options in which they'll be able to take advantage of the proposed reduction in the deduction up to the limit, and whatever funds that are no longer used to purchase property will be redirected toward other investments, or used to purchase fewer properties with larger down payments and smaller mortgages.
But WITW (Why In The World) should this or any other government have the ability to futz with our economic lives by this manner oif intrusiveness when there is a clearly better way via the FairTax?