ARRL editorial on BPL
 

http://www.arrl.org/news/features/2004/10/29/1/

excerpt
"If anyone doubts the legitimacy of the interference issue, consider this.
To protect aeronautical communications, the new rules establish numerous
frequency bands that BPL must entirely avoid. If the interference isn’t
real, why did the NTIA insist that the FCC take this step? Why do the new
rules establish exclusion zones and consultation requirements to protect
federal government, public safety, and certain other stations? We’re
looking forward to reading the Report and Order to find out whether the FCC
will require coordination around its own field offices, as the NTIA
thoughtfully proposed on their behalf."

The editorial is, of course, concerned with HAM issues and not with
shortwave listening.