If someone fights in a land controlled by no one (according to their borders) then no one should receive a bonus, however if someone fights in their own lands (their borders) they should receive a bonus because they have 'the people's' support.
__________________
-->Visit CGN!
-->"Production! More Production! Production creates Wealth! Production creates more Jobs!"-Wendell Willkie -1944
I think that would be normal to fight better in their home country...I'm not much into sport (To be hornest I hate sport in TV), but isn't it the same there too, like soccer players play best at the home stadium?
__________________
This space is empty... or is it?
yep, now with the new cultural system, your borders represent people actually living in the country side, outside your cities. so there definiately should be a "home arena" sort of bonus.
this should on the other hand depend on how densely populated your country side is.