Remove tool - how does it work?

I've never used Generative Fill, I feel that oversteps a line by retrieving unknown data from an outside image bank. IOW, calling home and bringing in external data that can turn out to be anything at all, and you have no control over it. That's certainly not very "creative" in my book.

I do use the Remove tool and Content-Aware Fill. They stay on the right side of the fence. To me they feel like the same underlying code, and they use only data from the current image. Even so, I try to limit the use, and always prefer to clean up the scene physically before pressing the shutter. These tools are last resort.

You may call me a purist, but that's not my main motivation. My motivation is final image quality, as well as total hours spent on the job. The result is always better by getting it right in camera from the start. As well as orders of magnitude faster.

And of course, sometimes a photo is documentation. Then you can't cheat.

I think all we really need to know is that it does not use Generative Credits.  From what I have been seeing in a lot of forum posts, is that a lot of people are using Generative Fill to remove unwanted image elements and are being disapointed.  Content Aware Fill is often a better tool to use, and it also doesn't use Generative Credits.  However, for smaller areas, and when more complex details are involved, the Remove Tool is often a better choice.

Regards Sensei, that was a catch all term that described improvements in various selection tools in Photoshop, as well as other Creative Cloud apps.  I am not sure that you should think of Sensei as the driving force for Firefly, Generative Fill, and even the Remove tool.  My impression is that these are a whole other animal.   The bottom line is that they are all done magic, so we just have to work out what spells work best any any given situation.