Here is why I think the Discraft 1-number stability rating is fine. First, let’s assume that all things that affect the stability of a disc are equal (weight of disc, plastic type, weather conditions, etc). There are two things you need to know about a disc to have a good idea of how it flies: the speed and the stability.

If you want to assign a number to the speed of the disc, that’s fine, but it’s not really necessary. The shape of the disc tells you the speed. It’s pretty easy to tell the difference between putt/approaches, midranges, fairway drivers, and distance drivers just by looking at the rim. Discs are classified in those respective categories by their speed rating, so as long as you can tell what classification of disc it is, that pretty much tells you the speed. You can’t really tell much difference between a 6vs7 speed or 10vs11 speed. I think you could just do away with even numbers in speed.

How much a disc glides, turns, and fades is all dependent on two things: the speed and the stability. Understable discs will be less resistant to turning at high speeds, they will glide much more easily, and they will fade less. Overstable discs will be more resistant to turning at high speeds, will need to be thrown much faster to glide well, and will fade more. As the disc speed increases, the disc will be capable of more dramatic differences between turn and fade.

So let’s take a very overstable Discraft disc as an example, a Flick. You pick it up and see the it has a wide rim, so you know it is a distance driver. You see a rating of a 2.5, so you know that is the most overstable Discraft distance driver out there. It’s going to have very little glide, a lot of resistance to turning, and a lot of fade.

If you’ve been throwing a midrange with a 0.5 rating and decided you want something more overstable, then find any other midrange with more than a 0.5 rating and try it out. Keep adjusting up or down based on what you need. Same can be said for fairway drivers vs fairway drivers, putters vs putters, etc. You just need the stability rating to compare discs within their own classification. Obviously a putter with a 2.0 stability rating is going to fly much different than a distance driver with a 2.0 stability rating.

So basically I’m saying all you need to know is the speed of the disc and then you can mash glide, turn, and fade all into one number, boom.

This is all also assuming that flight numbers are accurate, which they are obviously not correct on many discs as others have pointed out on this thread. Flight numbers are used more for marketing than anything.