If the shield is being jammed under his arm, wouldn't he still have to wrestle it's weight before being able to make that chop? She's literally forcing her shield in to him, while keeping her right side as far away as she can from him. In one post, she'd lead with her left, then continue pivoting in the current post. I think the two-post mark for most of my movements should be enough. I'm aware that Iolanthe has some bulk on her, but many of her attacks have taken multiple turns to execute. It took 2 just to try and sneak the spear under that shield.

Is the ruling really that Iolanthe must lose a hand? I'd figure bashing his funny bone would be enough. The full length of his sword shouldn't even be getting close.

I say this because - he's wielding the sword in his right arm, and the shield is in Iolanthe's left. He's leading with his right, she's leading with her left. The closes points between them are Iolanthe's shield, and Sigurd's sword. I don't see her defense faltering here, it's just so simple...

EDIT: Also, the fact her shield and his sword already clashed means they're incredibly close.  He never made an attempt to side-step a second time, to avoid how close that sword still should be to her hoplon.