You've got 4% accuracy from external sources (Legacy and spec). You had a ~14% miss chance with your basic attack and a 4% miss chance with your special attacks. Ergo, the boss has an 8% defense chance (104% accuracy reduced to 96% accuracy and 94% accuracy reduced to 86% accuracy), which is within the realm of what I've generally heard. Your parse is completely in line with what I was saying. Honestly, I find it likely that different bosses have different defense amounts, which is one of the reasons why it hasn't really been pinned down.
If that were the case then why does Master Strike/Dispatch miss some of the time but Blade Storm never miss? I would chalk it up to yellow damage being Force/Tech and using Force/Tech accuracy while White damage is Melee/Ranged and uses that accuracy.
You chalk the difference up to Defence chance and most people claim that Force/Tech never misses. Now given that Force/Tech has a base 100% accuracy and special attacks have a 5% bonus to accuracy, I can see where that (IMO incorrect) assumption would come from.