A very good question and I was thinking on exactly same line. The attached picture (
VIEW IMAGE) will tell you why its so. If you are not hardcore into science and don't get what all these factors are then its best explained by Capsid.
And yes, you are indeed right about
not thinking. I am closely watching IBD research for last 2 years (and seriously considering post-doc in IBD) and IMHO, it has long way to go. At this moment, all of us should only think one, how to control the symptoms and be happy :)