When it comes to the business of servicing subprime mortgages, it’s apparently better to be bigger. That was evident in the early part of this year, when a handful of giant servicing shops held a large portion of the outstanding loans in their collective portfolio. Overall, Inside B&C Lending estimates that the subprime market grew by 3.3 percent, to $1.24 trillion in outstanding loans, between the end of December and the end of March. That… [One data table included]