Edit... because I didn't see your post, until I made this one.
On that really long post above, try reading just the bolded parts.
It basically says we have no recourse as secondary users of our channels, in a nutshell.


Don't feel bad though... even wireless medical telemetry has only recently achieved
"co-primary" status on their frequencies. (Still shared with radio astronomers)
In event of interference, or possible interference (before setting up) co-primary users have
the same rights, and therefore must come to an agreement on switching or sharing channels,
generally with the help of a frequency coordinator.


Here's the general gist of the FCC designations: (Or rather, my understanding of such)

Primary
Has all the rights to their channel(s). Shares with nobody; accepts no interference. Full protection.

CO-primary
Equal rights with other co-primary services on same freqs. Must share. Moderate protection.

Secondary
Right to use, if the channel is free. Must accept *interference from primary users. No real protection.


* - with exception of stations proven to be operating improperly, or with spurious emissions




Edit... nothing to admire, by the way. The info is available at the FCC's site, ARRL, QRZ, and others.
I just have to go dig it up whenever I see the need. I usually post the whole RC part like that, so
anybody who wants to, later, can find it on a google search, or a search here on RCU

It's all summed up quite nicely in that "g" subsection:
(g)
...These frequencies are not afforded any protection from interference due to the operation
of fixed and mobile stations in other services assigned to the same or adjacent frequencies.