Do you believe we don't have an oversupply now?
In a speculative bubble, supply isn't so much the issue, over-demand is. As in demand for instruments of capital appreciation, not demand for homes.
If undersupply was the issue, then house price growth wouldn't be speculative by definition.... it'd be a genuine price rise due to lack of supply (think 1996-2001).
Even if we were perfectly supplied for genuine home occupation, demand for speculative instruments of capital appreciation warps the supply/demand curve. Remove that element of demand (i.e. lack of further cap. apprec.) and in theory you get a return to fundamental values.... not accounting for sentiment/herd mentality.
Incidentally, I think we are oversupplied. We'll see what shakes out of the tree once capital appreciation begins to disappear.