First thought:
My belief of the intent with the rule is that skirmishers, wagons and commanders would cause little distraction to the main target if such was the case. Also to deal with them is of little consequence to the main body of Cavalry i.e. the disruption to formation and/or force cohesion is not great, they can still be effective with a carry on through charge.
However not so against an artillery battery (2 guns are NOT a battery!), even attacked from the flank or rear or limbered. The cavalry would be spending time and effort, so cohesion and impetus would be lost, as they would be forced to deal with a larger and more problematic 'formation' (even unlimbered 4 guns cover a reasonable area and have a reasonable 'force' to be dealt with).
Therefore I believe a battery of 4 or more guns needs to be attacked in the EMP.
Second thought:
Pesky small cavalry troops blocking with ZOC. I too find it unrealistic and gamey even though we all tend to do it on occasion

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We could simply apply the same 100 strength rule as we do with skirmishers! We could however allow a 3:1 ratio. So a troop of 25 cavalry could block a force of up to 75, once the offensive force is over that 3:1 ratio then the cavalry cannot be used to block movement and exert a ZOC in such a way (even in covered terrain!), I'm thinking there for times when there are small elements still in action.
So a cavalry force of 100+ can be used to block even a large force (as any infantry force of the same size) e.g 1000+ troops could be blocked as 100+ cavalry still pose a threat when such a strength.
My 2c worth
