this is the first time i have ever called out another player for this kind of thing, so i dont get the "all the time" comment, nor do i consider one person's actions a conspiracy. i see this as an exploit and an unrealistic game mechanic as it currently stands.
maybe make it so once a to is started, it can be continued regardless of realm changes and the diplomacy changes that follow. this is much more realistic - while medieval lords could pledge allegiance to other figures as a means of protection, that doesnt mean that an army on their lands needed to stop fighting/looting/conquering.
That would be the most simple solution but is it doable? Maybe TO should disable allegiance change of the duchy as well.
