Between ACL 3 High and ACL 4 High, people depend on their procedural memories. Customary habits of a group of people are usually well known, but atypical habits are often particular to a job or living in a different community. When the performance of one activity is surprisingly better than the person's pattern of activity performance, an atypical procedural memory is often the reason. Simply asking, "Have you ever done anything like this before?" explains the connection to prior experience.