Modern Campaigns: noob query re. turn delta

[Stas_sche]

Re. the Modern Campaigns series (Fulda Gap, Danube etc.): is there any major reason why day turns last 3 hours and night turns 6 hours? Not a big deal---but was just curious if there was some special importance to these values? For example, why not 1-hour turns for both day and night? The game scale is 1-mile per hex and units not in travel move usually move 1 hex per turn (i.e. 1 mile in 6 hours at night).

The turn difference between night and day are very simple:
1. Human beings require to sleep sometimes; Usually at night. So the sleep time is incorporated. 
2. It is harder to move/drive at night (using headlight is forbidden during the war). So it is simulated by longer turn with the same number of the action points.

Why not 1 hour? Playability and rules. For example, if the turn is 1 hour and a unit can move only one hex per turn, the disrupted unit will become immobile (as it uses 3 times more action points to move due to Distraction).