To answer this question, we need to understand the difference between latency and delay. Both are time delays but latency is unwanted time delay caused by A-D conversion, D-A conversion and DSP processing. In the A Series this is 1.7 ms and it cannot be avoided. This is a very low value for a DSP studio monitor and the practical implications of this are negligible. Even the most time critical listeners tested (they were blind) cannot hear latencies of less than 5 ms.
The delay value set using A Control is a deliberate delay applied to compensation for positional differences in the room with resolution of 0.1 ms, which is approx. 3.5 cm = 1.4". For example, if the centre loudspeaker is closer than the left-right loudspeakers by 10 cm then it can be delayed by 0.3 ms. The maximum delay possible is 10 ms which is the same as 3.44 m (11' 3"). This is more than enough for even the largest control rooms.
One additional use for delay is lipsync to align audio and video signals. These delays are much longer and often in the region of 2 frames for a flat screen. 2 frames is 80 ms for 50 Hz countries and 66 ms for 60 Hz countries. Even more lip sync delay can be needed for processed signals in broadcast stations. The A series does not have enough delay for lipsync.