Sure, my point is that the metric "minimize mean number of guesses to win" isn't axiomatically the objective function: the 6 threshold already suggests that many people would rather have a "guaranteed 6 and average 5" rather than "average 4 but fail 5% percent of the time".
If someone considers a 4 to be a soft-failure then they will prefer (3,6,6) to (4,4,4) even though the latter is a lower mean number of guesses: it's a higher count of 4+ 'failures'. The strategy that considers (3,6,6) a better result than (4,4,4) wouldn't guess "dream" in the above example.
Maximizing information from each guess until the answer is down to two candidates minimizes the number of guesses needed to win.