AddRotation nodes won’t use increments smaller than 0.0115, no matter world, relative or local rotation.
I am not sure its a bug, I think its because of how the floats behaves when you add a large and a very small value together, it will round due the none-uniform distribution of accuracy.
You could create a variable and accumulate all the increments you need to add and simply just add that variable.
Eqric is correct, because of how the floats behave, when you add large and very small values together, it’ll round due to the non-uniform distribution. This is called ‘Float Point Error’.
Let us know if you have any further questions, have a great day!