Imagine someone new to disc golf. How do you explain to them how to tell if a DD disc is a putter, midrange, driver. They have to look it up on a chart or list. How can they tell which is more stable between a Judge and a Warden? They have to look it up.
Now look at how the Discmania system is consistent and tells you not only what class of disc it is, but also the relative stability.
Which is more stable, P1 or P2? Oh, the bigger number. That makes sense. Now I know that a P3 is a more stable disc than the ones with smaller numbers. Oh, and since it is a "P" then I also know it is a putter without having to look it up.
If a P5 is ever released, you already know it is 1) a putter and 2) higher in stability.
If DD releases a new disc and tells you the name, you have no idea what kind of disc it is or how stable it is.
What is tough with Discmania's naming is that it only really works for Speed 9 and down. Then it becomes a crapshoot in their distance drivers. Without looking it up, can you logically tell the difference between a CD (10 speed), CD2 (9 speed), and CD3 (11 speed)? Or how about a DD (11 speed, 0 turn), DD2 (13 speed, -2 turn), DDx (12 speed, -1 turn), and DD3 (12 speed, -1 turn)?