I find communities that constantly add gratuitous "YMMV may vary - everyone's body is different and no one really knows anything" tend to have less groupthink and are generally more adaptable both to new research and old research. The "YMMV" should be obvious in any discussion about individual humans, but when communities don't emphasize it constantly, people start thinking that "90% of patients benefit from $INTERVENTION" somehow means that they should just shut down discussion around the other 10%.