Measuring temperature at Kilchoman

I was interested that the Kilchoman distillery was using analogue thermometers. The resolution is +- 2 degrees Celsius. Also note that they are cross-wired: the upper thermometer is connected to a sensor lower in the tank so the temperature does get lower as you go up the tank. I wonder if the use of analogue is because they have a more averaging effect on the reading. In the era of high resolution digital instruments, the reading can seem to go up and down rapidly. But how relevant would that be in a large tank where local fluctuations wouldn't give an overall picture? I did see an examination answer recently that suggested that an analogue scale was better for monitoring a reading that needed to be kept roughly constant because you can draw on a line to show the necessary reading and that it easier to understand.