Industry experts are concerned that significantly raising the standard federal income-tax deduction could make the mortgage-interest deduction less valuable and hurt the housing market. The Republican “blueprint” for a massive overhaul of federal income taxes proposes boosting the standard deduction from $12,600 to $24,000 for joint filers. This could mean fewer taxpayers would itemize their deductions and claim the MID. The Community Home Lenders Association opposes...