My point is that you should not have to go through to such an extreme extent to protect yourself from rouge cavalry to begin with.
Due to various questionable submissions regarding the functionality of Scourge of War - Waterloo, it is my intention to come back to this discussion again.
From my experience, it is still a good means, but not necessary to try to build a complex artificial formation to avoid cavalry raids on artillery batteries. The self-protection of the AI battery commanders has been well implemented. In estimated at least 60% of the cases, the artillery withdraws in time, unless the aggressor is intercepted by cavalry anyway.
In about 20 to 30% of cases, more or less high losses occur. A complete extinction is the exception and is anyway only in a variety of squadrons into consideration.
I think that's about realistic.
As far as high losses in batteries by cavalry raids should be the rule, so I have to assume faulty settings.
If the AI or even a human player in multiplayer battles selects the setting "hold to the last" or a very aggressive stance, then the artillery in question will experience excessive passivity or, in the latter case, excessive risk-taking. The same applies, if a human player keeps the battery under direct control. It seems very well, that the AI of divisional or reserve arty, set their batteries to "hold to the last" stance. This should always be checked and adjusted accordingly.
Recommended for effective self-protection on the part of the AI is a medium stance such as "defend" or "probe". To make sure the cannons being secured in case of closing Cav, it is also possible to give order to move them manually or order an emergency withdrawal, if the certain battery is part of the own OOB.