Q1: In gaintable=['%s.tsys.fdm'%(vis.split('.')),'wvr_%s.cal'%(vis.split('.'))], what is the  stand for?
Q2: Trivial question -- what is the reason for the timesort here - just convenience?
concat(vis=cal_south_vis, concatvis='Antennae_South.cal.ms', timesort=T)
Q3: In the NGC3256 Band 3 calibration guide, we start by flagging the autocorrelations. If the observations had included an "OFF" position, would we have been able to use the autocorrelations to make the equivalent of a single-dish map? If not, what other observations and tools would we have needed?
Q4: Can you explain the meaning of message like "Out 0"?