Industry observers are warily eying the potential impact of a bill unveiled last week by a senior House Republican that aims to encourage private capital into the residential mortgage secondary market without the need for Fannie Mae or Freddie Mac. The Private Mortgage Market Investment Act, drafted by Rep. Scott Garrett, R-NJ, would create a heavily regulated mortgage-backed securities market made up solely of private entities that would function with no federal guarantee at all. Garrett, who chairs the House Financial Services Subcommittee on Capital Markets and Government-Sponsored Enterprises, said his proposal will...