This is particularly important in conditions where sky variations are adding noise to maps through fluctuations in the system calibration. For point sources, there is a gain in speed of a factor of 2 from the fact that you can chop on the array. The present JCMT system using the DAS gives a minimum dump time of 3 seconds. This is over and above the other factors described above. Display and reduction of maps will be done in realtime, allowing fast checks on system performance, observing status and astronomical results.
Redundancy is available, if for example one mixer or one correlator sector fails.