For example, WTF are you talking about with the "original five years ago"?
I was speaking of the plugin.
A change of 0.025 (which in pratice is much less because it is 0.025 of the index on the left) produces basically inaudible results
[edit: I wrote wrong algo 1, I meant 32 although you can use algo any where they are both carriers]
Using Algo 32, turn off all operators except one and two.
Leave OP1 at 1 and set OP2 at 1.01 (you will need to use something other than Arturia)
Using C3, as you change from 1:1 to 1:1.01 you will hear a reinforced sine take on a beat frequency. Changing to 1.02 pretty well doubles that beat frequency. The difference is very audible and if you move from C3 to C2 you will notice the beat frequency 1:1.02 move down to C2 to give roughly the same result as C3 at 1:1.01 We use such a change to move our BFO up and down the keyboard as preferred by our choice of register.
Using an oscilloscope and you can see and hear the stark difference between 1:1, 1:1.01, 1:1.02
The engineers at Yamaha were neither stupid nor pedantic. They had good reason to use such fine detail.
Now I first used a DX7 in 1986 and my ears have taken a beating since I started playing in 1968 but I can still easily hear that difference.