The typical immature joke would be to point out that the number sixty-nine can be lewd in the minds of immature individuals; I assumed that somebody would make a joke about it eventually. The humor is that I pointed out the 'normal' part of the title rather than the '69', which would have been expected by those expecting some sort of sophomoric joke. In essence, it was the unexpected that would have provoked laughter, amongst those who see the innuendo in the title of the thread initially.