“The stakes are high. The borrower with the 2.6 percent ARM who was paying 4 percent initially probably has a maximum rate of about 10 percent and a rate adjustment cap of 2 percent. That means that if the one-year Treasury rate jumped overnight to 10 percent and stayed there, the ARM rate would adjust to 4.6 percent at the next adjustment, 6.6 percent one year later, 8.6 percent the year after that, and it would top out at 10 percent one year later. Since the fixed rate would escalate with the Treasury rate, the opportunity for a profitable refinance would be lost.”