On Mon, 5 Jan 1998, Henry J. Cobb wrote:

The best way to think up an idea that nobody in their right minds would
touch is to ask the wrong questions.
For example, in the Ranmaverse....
Ten years before the start of the series Genma was either taking Ranma
around to meet Ukyou or he was the student of Happi.
The simple, easy answer is that Genma trapped Happi in the cave after
Ranma (and Akane) where born and then came home and took Ranma on the
training mission.  (He was inspired in the art or some nonsense).  So the
story Genma and Soun related when Happi reappeared was simply off by a few
years.

Well, my personal idea (to appear in Tendou 2/3 eventually) is that the
timeline is such that Genma pretty much had to be training under Happosai
_at the time he married Nodoka_.  This explains why Nodoka has strange ideas
about being manly meaning peeking at girls--she learned it from him.