Could you test your new patch of glass against the old by painting a piece of wood black or use a piece of walnut and laminate them at the same time? The non transparent weave really shows against the dark.This problem reveals itself almost immediately in my limited experience ,if you can see it in a low angle light. I do not have a temperature controlled workspace and have switched to 4oz instead of 6oz and that seemed to help. One thing is that if after mixing and spreading the first small batch and you can still see the dreaded white weave do not keep going hoping it will wet out. I don't think this is what happened to you but have read about the issue of putting to much tension on the cloth during roll out . This can cause micro fractures that result in a starring effect.

I am always surprised to see non transparent strands along the length but not the width. I hope that someone with more experience with this phenomenon will weigh in, for me it is most common problem. best rh