Nick — The "most" would probably be the infinite number of ancient "courses" where the start of play was up to the participants — there being no real "holes" per se. In this case there are millions of tee locations! Of course, I have not seen this personally, but there is decent cause to believe that golf's first courses were of no organized system...certainly none with "tees".
The idea of multiple teeing grounds is actually quite entertaining...holes play in exponential ways when you set courses up in different ways. (Although I suspect you are annoyed by the multiple colors, distances, and confusing yardage equations.)
Desmond Muirhead designed a hole with about 25 tees. It was a par-3 and I recall the tee complex being about 100-yards in one direction and another 100-yards in another. Sort of "V" shape. I do not know how many "official" rating pointe (distances) the course is measured from.
I can tell you that State golf associations are now rating many more "courses" than they used to. For example, we now see owners/operators requesting official ratings for up to 8 or 9 different "course ratings" at one golf course...
> Forward
> Forward/Seniors combined
> Seniors
> Mid Tees
> Seniors/Mid Tees combined
> Regular
> Championship
> Regular/Championship combined
> Tournament
We are also seeing a rating be done for kids tees — typically a distance rating that uses forward tees and, in many instances, points forward of forward tees where kids might have more fun.
We are working on a course currently that will have official ratings, but the owner is seriously deciding to not have any tee markers at all. The only markers would be permanent markers at each tee — which is two or three teeing grounds per hole.