Does a No Contest fight count as a title defense? Does a DQ count as a title defense? How long does the match have to be scheduled for to count as a title defense? I say no to question #1, and yes to question #2. Question #3, I'm not sure.
I'd count DQs, probably not no contests, but maybe depending on the reason. I don't think the scheduled length really matters.
I don't think the scheduled length of a title fight matters. There have being all manner of scheduled round s .Look at Dempsey v Tunney ..10 rounds .Johnson v Willard was I believe 45 .So it could be anything .
I'd probably look at the reason. I suppose there's no reason standards shouldn't change over time. It's often better to understand things by the rules etc. of the time than now.