+1
This also makes a lot of sense for another reason besides the loyalty "recharging" effect - while in the kings stack they can't start a civil war. It also makes sense in some cases to round up the "traitors" and herd them into one backwater province where they can't do any harm and send the spies in there and let them have a it...
If civil war is imminent however and your royal stock are a lot of chinless, perverted cowards, madmen and drunkards, it's wise to instead round them up, separate them and help the civil war along a bit, then when it breaks out - back the rebels and you have a new dynasty. Seems like an exploit but not the worst by any measure...
Civil wars and the lead up to them, are one of the most interesting dynamics of the game - sadly missing in later titles.
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