Most spears would get stuck, yes, but I suppose I figured the triangular shape of her spear would be better described as a lance. There is no bulk at the tip to get stuck, if it went in clean, it'd be just as easily withdrawn. The superheated blade would serve as a lubricant of sorts, making it hard for wood to clamp on to the blade. The end result would've been a loss of a shield, and given Iolanthe's abundance of these, she'd be able to defend herself easily whilst tossing the log aside, or simply retracting her arm. Of course, Sigurd wouldn't have to worry about damage to that arm had he worn a wooden shield, so it'd have done little for either of them. 

As for the scaled shield... now that would serve as more of a disadvantage if Iolanthe's spear got stuck in there, cause it'd take too long to peel off the scales, giving Sigurd room to retaliate. That's what I wanted to know. She'll find that out later if we get to a scene like that.

If you've read Iolanthe's backstory, you'd figure that I've also studied ancient history. This fight wouldn't have taken place in reality, given the timespan between the early Roman empire, and when the Vikings began raiding Saxony and Frankia. This is like a special episode of The Deadliest Warrior!