I believe this may have been asked and answered yesretday. The question is familiar. Notice must be sent for subpoenas for records or deposition. Notice need not be sent for a subpoena for trial but there may be a requirement of disclosure of witnesses.
Agreed. In addition, if it's for records I send them a copy of what I get. I do this because when I'm on the other side of this, I like getting copies instead of serving a 204(a)(4) request.