1. He stepped forward to thrust, stepping on her foot was a bonus born from the fact that she first had to rise before she could shift her weight to slip her leg, where-as Sigurd could just step forward.

2. Her guard was broken as soon as Sigurd's shield slammed into it, helped along by her complete lack of resistance (awfully convenient that she knew matching his strength would hurt her). His shield slam was planned while Iolanthe was still dropping down to try and bend Sigurd's sword, so it takes precedent over the leap she attempted in the following post.

3. Sigurd had already made plans for her to try and pull her shield back, he had no issue with slamming his shield behind her own instead, so pulling back would make very little difference and he wouldn't have overextended (as he was holding the shield at a slight angle conductive to catching her shield should she pull back, the only logical defence.)

4. Shield's in front of her face until it's not, so any defence must be made without the benefit of any clear line of sight. 

5. The crossing of his arms is unimportant, he can strike perfectly fine under his arm. Dodging the opposite side of his sword arm is actually conductive to his thrust in this case, if she had dodged the opposite direction Sigurd's shield would be in the way, as it stands striking at a leftward angle is exceedingly easy, actually preferred to her being straight on. 

6. Not really.

7. I expect you to come up with something amusing, as the strike is a killing blow if left unchecked, perhaps the only one that can plausibly be launched against your character's tank like armour.

8. Yes she did, she took no precautions against Sigurd's shield slam, in fact she did the opposite and dropped her weight by throwing her own shield downwards. Unless your character can completely reverse physics, not to mention her own momentum, she was not going to be able to move her heavy shield out the way.

9. I didn't complain because you finally did what should have been obvious about eight posts ago, and got the hell out of dodge. Unfortunately, rather than simply slipping the leg when Sigurd struck at it you actually closed on him, which was monumentally counter intuitive. You've finally done what made the most sense, but at the worst possible time in the worst possible situation, by first having to rise before being able to pull back. In actuality what would have been most beneficial (and therefore 'what I want') for me would have been if your character was not somehow aware that Sigurd's shield was flying in (despite no prior observations being made) or that she was not aware that his arm would be unduly powerful and tried to resist, breaking her own arm or at the very least being surprised. Instead you somehow turned having your arm wrenched and your guard completely opened into an advantage by having your character lunge backwards. However, it still made sense, hence no complaints. 

Hopefully that covers all your arguments surrounding 'critical details' though I'm not overly optimistic.