Anxiety-provoking situations must be tolerated without such behaviors in order to demonstrate that they are innocuous in and of themselves. There is evidence to support both theories. There is also evidence that safety behaviors don't interfere with exposure at all. There are also various difficulties in disentangling the two theories for the purposes of testing, and I'm not sure they're even very disjunct. I have reached the conclusion that rather than distraction and misattribution, we should be focusing on a different distinction.
Some behaviors prevent the gathering of disconfirmatory evidence.
Others, however, do not. If a subject wears armor to prevent spider attack but can still see that the spider is not attempting to approach hir, this is a misattributional behavior that leaves the opportunity for disconfirmation intact. My proposed split is thus between escape and coping behaviors. Our study tests this by exposing spider-phobics to big, scary tarantulas. The coping group gets a shield that will protect them from attack, but which does not restrain the tarantula.