>>536757118
Cassius does that because fundamentally he doesn't want to lose estelle after losing his wife. Considering he knew Joshua would probably eventually ghost him he is largely thinking estelle might die if she gets too powerful enough for her brains. The fundamental force driving the conflict with estelle and him in my own musings is that thanks to her ability to read the divergent laws like Jessica estelle would naturally become someone who Cassius wouldn't be able to keep away from the society
Ward estelle from the society, she leaves
Let estelle investigate, Joshua leaves.
Cassius can't win. In canon though estelle is a lot easier to handle. She's dumb as a sack of bricks and doesn't have a cheat ability like Claire, cruise, campy or lechter to bail her out.
Personally I would be fine with her being this weak if the games made it a point to have her win the duel with Joshua at the end due to the strength Joshua has being unable to be controlled by Weissman