I agree. Nothing will stop any of my critters either no matter how "in the blue" they are. I have had a couple miss the rat once or twice when they are heavily in shed though. The clouded eye caps can make it somewhat difficult for them to see and therefore they have more of a tendency to miss their strike.
If your boa was striking, missing, then hissing, I would guess that he was just frustrated that he was missing his mark and not actually refusing. But even so, it won't hurt him to wait until after he's shed to feed.![]()