How did No.6 know this would happen, should the assassination/execution attempt have been successful, that the Village would take mass reprisals, a never to be forgotten deterrent upon innocent people? After all the heir presumptive did ask No.6 what else would he expect them to do?
Perhaps No.6 thought that this would be the most likely case of events. After all the villages administration would be expected to find the culprit for the assassination of the retiring No.2. And maybe the citizens themselves would expect it, but questioned, how many of the citizens could actually point the finger at the little watchmaker-No.51? After all only the heir presumptive, No.100, the Watchmakers daughter-No.50 and No.6 who knew of the assassination plot!
What was suggested by No.6 sounds like one of those purges we hear so much about, this whilst carrying out those mass reprisals. No.6 knew the Village, he knew what those in charge were capable of. The death of the retiring No.2 might have been an execution by his own people. But someone would have to have been found accountable, and with the watchmaker holding the detonator he would have been easy meat.
But then having said that, if the culprit had been found, that being the little watchmaker, then how would the new No.2 account for those mass reprisals? Unless of course the little watchmaker-No.50 was to quietly disappear, and his daughter with him! thus giving the new No.2 the opportunity to go looking for non-existent assassins and thereby carrying out the purge!