OP has a very interesting point. At a time where there was no rampant house price inflation, it was reasonably likely that a borrowers financial circumstances would probably not differ very much or even significantly imrove from date of signing the contracts to completing the transaction anything up to 18-24 months later when they needed to draw down the loan.
Now that people are borrowing so heavily and the market is uncertain should they be able to withdraw from a contract if their circumstances change? Would purchasers use this as a ploy if they simply changed their minds? Or should they just not buy a house? And should builders be lumbered with a property that now no-one else may want to buy?
Its all ahead of us.
mf