Stockdam,
We have ADAS recorders for flight test on our aircraft as well as the Regulation FDR - while some FTEs like to have a tape recorder to fuss over, the main data collection comes from the unmonitored hard drive. There may be test cases where monitoring of the actual recording is required - say in extremely high sampling rates - but in reality the modern recorder doesn't need it and especially so if it's a single place aircraft or reduced crew for risk reasons. All worries about parameters, data rate, scaling etc should be taken care of before flight to remove the need for monitoring the data flow.