I know for a fact the Navy and USMC use the frequencies from 6700-7000 for not only voice comms, but CW, RTTY, SITOR and other modes. The warning was "stay away from the Hams as much as you can, BUT.......if you need to do a short test, and there aren't any strong signals nearby, go ahead for a short time". For the most part the Navy/USMC don't typically even listen before tuning up a 5kw TRAC or a low power transmitter. The Op is told by HQ's what frequency to use, and they do. Unless there is severe interference to the military comm, they won't bother to find another freq.