This is true; however, based on my experience the interviewers are usually very dissatisfied to discover such "one simple trick", the implicit expectation being that you are expected to gruel through the problem without abstractions.

This part has been always funny to me, because the same interviewers also simultaneously expect knowledge of abstractions in their "low-level design" phase of the interview, where irrelevant abstractions are added in to satisfy some odd constraint that would never come up in the real world.