Hi,
very good question:
ease float is time based. you ease a float in 2 seconds, with lerping, it's a constant catch up of the value with a define "speed" to get there.
so if your float is a moving target, you can't ease because you are limited in time, you must lerp to continously try to get closer to the target smoothly.
Does that make sense? that's exactly why on that other post, I recommand not using tweening engines to follow moving targets of ayn kind, because the "easing" is a finite somehow, else it doesn't make sense, how can you have a "sin in and out" when it nevers ends...? that's where lerping comes in, because you can let it run, and your target can be moving or not. the "easing" you get it simply defined by the amoung of lerp you inject, the smaller the more time it will take to catch up and the smoother it will be, close to 1, it's almost instant as if it was attached to the target.
Bye,
Jean