How do contextual applications really get considered?

I’ve read all the information on the website about how contextual data is used, and the two grade lower offer that could result from a contextual offer. This bit is clear. But it’s still not clear about the way in which the applications are assessed, when say that the contextual application is ‘considered in context by an admissions officer’ what that practically means when deciding who to give offers to. Eg if someone applies with contextual AAA predicted would they still compare unfavourably to someone non contextual with A*A*A? Does a contextual applicant get given some kind of boost to their application to consider it fairly with others?

Does anyone know or has anyone got experience of the contextual offer admissions process at St As?