My investigation of this kind of code showed that it won't have an effect on the AI. The engine will ignore it at best. At worst it will break the section it is contained in and force the .exe to use internal defaults.
You'd have to come up with some pretty amazing battle script to get what you want. Sorry but you will not achieve it via config_ai_battle.xml.
Check out the historic battles' scripts in vanilla. I warn you though, you're probably looking at doing a huge amount of work if your goal stays the same. A single battle wouldn't be so difficult to script, but with campaign stuff you'd essentially be replacing the AI with one you've scripted.
edit:
It just occured to me you can do something like this:
Code:
<outflank-analyser>
<unit-priority>
<vs-behind-stakes>100</vs-behind-stakes>
<vs-cavalry>200</vs-cavalry>
It might help a little, units chosen for flanking are more often attacked. But revert to a vanilla config_ai_battle before proceeding, or at least one with none of that code in your post.