How many tuplets?

Recently, I have been thinking about the measures used in the West African drumming. Most of the rhytms are 4/4 or 12/8. Some of them are (or at least have elements of) 6/8 and, to a lesser extent, 9/8.

I usualy refer to these rhytms as "fours", "twelves" and etc. Some people, on the other hand, refer to them as "straight", "triplets" and other rhytms. Now, the last two words don't seem to be chosen adequately, but there is a strong logic in this. I just realised this is quite a good point.

In fact, West African music, when played by expert musitians, often can't be classified neither as a 4/4 and neither as a 12/8. Some basic idea persists though. But in either case there is always something (a solo if not anything else) that is playing some sort of triplet, duplet or whatever.

That said, the biggest difference in rhytms seems to be in how much of the tuplets (duplets, triplets, ...) are being used. This would mean that most of the times it would be enaugh to specify a number like 3 or 4. 4 could mean 4 duplets (4/4 rhytm) or 4 triplets (12/8 rhytm), 3 could mean 3 duplets (6/8) or 3 triplets (9/8). This would embrace every African rhytm I know, since you can use other numbers too.

This also shows what I was thinking about when I came to this idea. I was looking at the astonishing similarity of the 6/8 and 9/8 rhytms. I will leave this to some other time.

One final question remains: "How to know which tuplet to choose and when?" I guess the question could be turned around and it would be: "What is the feeling you would like to express?" There is no need to discuss this.

So, on my opinion:
while these two parts belong to the same song

these two do not.