"Because the banks are holding many of these distressed assets and if the Fed lets the price fall the bank's balance sheet blows up"
Bingo.
If the mortgage holders have no choice but to flood the markets with many thousands of listings at 'sell at any price' or something like it, then the game is up. Game over. Hence, the float. Honestly, it's a very smart way for the government to manipulate the market - they are the only 'game in town'. The Fed is ensuring that there will be no 'run on the bank', be it financial or real estate.
Bingo.
If the mortgage holders have no choice but to flood the markets with many thousands of listings at 'sell at any price' or something like it, then the game is up. Game over. Hence, the float. Honestly, it's a very smart way for the government to manipulate the market - they are the only 'game in town'. The Fed is ensuring that there will be no 'run on the bank', be it financial or real estate.