Understand that the other party is also busy. Respect the DC's time. Talk to each other. Talk to the doctor, not the staff. The doctor can then return the call with the answers in hand.
Documentation is annoying, but critical.
Provide the information requested, and highlight relevant portions of your notes. If you believe you have already sent a particular piece of information, copy it and highlight the part that answers the adjusters questions. Provide complete treatment plan, and include projected end dates. This will help the adjuster understand you know what you are doing, that you have a goal in mind, and when the case is likely to be completed. Ask only for documentation you will read.