Here is a video to demonstrate what I mean, in case my description is inaccurate. Basically, I wanted to follow a tutorial on skin painting, which relied on laying down color in important areas first, and then blending them together by sampling color averages and painting between sections. This means a lot of color picking / eye dropping, and if I could use the modifier for the brush tool it would be super smooth and quick. If I have to switch to the eye dropper, then sample, then double check the new color is applied, then painting, then resampling.. It would be an awful way to work.
color_picker_demo.mp4