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What you really are is a Bunburyist. I was quite right in saying you were a Bunburyist. You are one of the most advanced Bunburyists I know.
— Algernon

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The unusual label is repeated with growing confidence, ending in the claim that the listener is an especially advanced example. That progression makes the accusation sound like recognition of a skill. The speaker also enjoys being proved right about a judgment already made.
Context reviewed