Buried in one of his articles was a very interesting "rule of thumb" that would save me time in just about every KoW game I played.
The 50mm "Rule"
When units are pivoting - whether for movement or to charge - they must end their pivot clear of intervening units (Note: countercharging units have a more complicated exception covered in the FAQ). Generally you will find that units are at least 1" from enemy units and likely (though not necessarily) that from their own units.
Now say you want to pivot and move away (or charge). The ability to do this is based on the dimensions of your unit as a pivot must be around the unit's centre point.
Given the following scenario where Unit A and B have a gap of 1" is a legal pivot achievable?
Well this is where the 50mm rule comes into play!
As long as the width of the unit is NO MORE than 50mm larger than its depth, a legal pivot can be made.
Taking Large Infantry as an example, a Regiment is 120mm x 40mm while a Horde is 120mm x 80mm. Based on the 50mm rule, the Regiment is not able to pivot given a 1" gap (80mm > 50mm) while the Horde can (40mm < 50mm).
This rule can then be applied to all units:
Those units marked in Red can not pivot legally with a 1" gap between units while those in Green can.
It seems a bit counterintuitive in places e.g. an Infantry Regiment is more agile than a Troop, while an extra long base makes Large Cavalry (Chariot) Regiments more agile than non-Chariots. All this assumes sufficient gaps to the side.
The same rule can be applied with proximity to the enemy but remember you must be charging in this case.
Anyway hopefully the rule of thumb will help you in your games.