Como não houve (a partir de A Dance With Dragons) quaisquer capítulos da Roose PoV ou qualquer capítulo onde ele falou sobre essa batalha, nós podemos apenas especular sobre seu raciocínio.
Este artigo especula, com quantidades variáveis de Evidência de que Bolton, apesar de não ser exatamente um aliado dos Lannister desde o início, era certamente desleal com os Starks, tentando promover suas próprias ambições enquanto minava a força de seu suserano e seus leais vassalos.
Em relação a essa batalha específica, podemos ver duas citações interessantes do livro que mostram que as forças de Bolton não sofreram tanto nessa derrota:
He glimpsed the bull moose of the Hornwoods, the Karstark sunburst, Lord Cerwyn’s battle-axe, and the mailed fist of the Glovers ... and the twin towers of Frey. (AGOT, Tyrion VIII)
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“My liege, we have taken some of their commanders. Lord Cerwyn, Ser Wylis Manderly, Harrion Karstark, four Freys. Lord Hornwood is dead, and I fear Roose Bolton has escaped us.” (AGOT, Tyrion VIII)
Esta não foi a última vez que as forças de Roose Bolton se separaram do restante dos bandeirantes, para sua derrota. Na Batalha de Duskendale, que era a idéia de Roose Bolton (para a qual ele não cometeu nenhuma força), ele havia similarmente sacrificado a vida de seus "aliados" em oposição aos seus:
“Tell him to put the captives to the sword and the castle to the torch, by command of the king. Then he is to join forces with Robett Glover and strike east toward Duskendale. Those are rich lands, and hardly touched by the fighting. It is time they had a taste. Glover has lost a castle, and Tallhart a son. Let them take their vengeance on Duskendale.” (ACOK, Arya X)
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"As for Stark, the boy is still in the west, but a large force of northmen under Helman Tallhart and Robett Glover are descending toward Duskendale. I’ve sent Lord Tarly to meet them, while Ser Gregor drives up the kingsroad to cut off their retreat. Tallhart and Glover will be caught between them, with a third of Stark’s strength.” “Duskendale?” There was nothing at Duskendale worth such a risk. Had the Young Wolf finally blundered? (ASOS, Tyrion I)
O resultado foi uma grande derrota para o Norte:
The eunuch smiled a silken smile. “I have such delicious tidings for you all, my lords. Yesterday at dawn our brave Lord Randyll caught Robett Glover outside Duskendale and trapped him against the sea. Losses were heavy on both sides, but in the end our loyal men prevailed. Ser Helman Tallhart is reported dead, with a thousand others. Robett Glover leads the survivors back toward Harrenhal in bloody disarray, little dreaming he will find valiant Ser Gregor and his stalwarts athwart his path.” (ASOS, Tyrion III)
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When they brought him word of the battle at Duskendale, where Lord Randyll Tarly had shattered Robett Glover and Ser Helman Tallhart, he might have been expected to rage. Instead he’d stared in dumb disbelief and said, “Duskendale, on the narrow sea? Why would they go to Duskendale?” He’d shook his head, bewildered. “A third of my foot, lost for Duskendale?” (ASOS, Catelyn IV)
Não só isso, quando Roose Bolton deixou Harrenhall para se juntar aos Stark, mas mais leais bandeirantes caíram:
Two-thirds of my strength was on the north side when the Lannisters attacked those still waiting to cross. Norrey, Locke, and Burley men chiefly, with Ser Wylis Manderly and his White Harbor knights as rear guard. I was on the wrong side of the Trident, powerless to help them. Ser Wylis rallied our men as best he could, but Gregor Clegane attacked with heavy horse and drove them into the river. As many drowned as were cut down. More fled, and the rest were taken captive.” (ASOS, Catelyn VI)
A cautela de Roose Bolton foi comprovada em todas essas interações. O que deve ser questionado é sua lealdade. Que o evento do casamento vermelho provou.