Sorry, just had to mention that this comment "I also react to ovens that are normally used for gluten baking. Not everyone here does, but there are many that do--including my boyfriend" is not substantiated. (No medical or scientific articles to back that up.)
It's been questioned before. No offense to the OP, she's given me good advice before, but I personally do not agree with the oven advice. I'm very sure it it irrevelant.
I react to food from shared oven too. It was the only intolerance I discovered while keeping a food diary, only at that time I brushed it off as total nonsence.
Unfortunately my body don't need any scientific evidence to get sick. It even goes further than that and gets violently ill from grain products that are scientifically proven harmless to celiacs.
I'm sure the oven advice is irrelevant to most celiacs, but not all of them and unless you try it you cannot know which of the group you belong to.