Oh gods, Quintus Servilius Caepio and the river fiasco.
He's refusing to acknowledge Gnaeus Mallius Maximus as supreme commander of the army even though he's theoretically supposed to because Servilius Caepio is the commander from the previous year and the current year's consul, Mallius Maximus, ought to supersede him. Mallius Maximus is an upstart New Man according to Servilius Caepio and they're trading nasty notes back and forth threatening each other with charges of treason.
Servilius Caepio has just finally agreed to cross the river...and is making his own camp instead of joining forces. He's making camp just far enough away to be useless to everybody. This will all end in tears, won't it? [Aside: I know it will; I peeked at Wikipedia to confirm that this wasn't made up. It seemed on par with the Roman political posturing to date in the book, but you never know. So, yep, this totally happened.]