The massive new investigative report on Fannie Mae’s accounting and management scandals may not change anyone’s mind about reform of how the government-sponsored enterprises are regulated – but it gives both sides plenty to talk about. GSE critics were quick to say the 2,652-page report from investigators hired by Fannie Mae shows the government needs to dramatically strengthen the regulator’s powers. But Fannie Mae supporters say the investigation headed by former Senator Warren Rudman turned…