The method is the same, it just looks different when n=1. I.e. the method is "wait until you see something particularly anomalous occuring, probe, see if the reaction is human like". The more times you say "well you can't count that as anomalous, an actual person can look like that too and a bot could try to fake that!" the less effective it becomes at blocking bots.

This approach clearly blocks bots so it's not enough to say "just don't ever do things which have false positives" and it's a bit silly to say "just don't ever do the things which have false positives, but for my specific false positives only - leave the other methods please!"