here's a great article / video on gut health by Dr. Bryan Walsh
http://www.precisionnutrition.com/fix-gut-fix-health
i've come to this conclusion myself based on various things i've read on the subject as well as the information given to me by several doctors i've consulted with (Dr Bryan Walsh is one of them)
i also deal with gluten intolerance myself
what i'm trying to say is, if you have an autoimmune response to gluten, my personal opinion (again based on what i've heard) is that it isn't a good idea to ingest it, even in small amounts. it just makes sense to avoid it entirely if your body reacts negatively to it
personally, i would opt for certified gluten free oats vs regular oats, especially if i was eating them on a daily basis - this is because i've been diagnosed with gluten intolerance and my tests have shown an autoimmune response to the protein.
if you're simply intolerant and don't have an autoimmune response to gluten, then you're probably right, trace amounts may be insignificant
the question is, how many know about the level of their own gluten intolerance, if any, and what a best practice may be