Hi,
Ever since Lightroom's spot remover was enhanced to allow drawing a shape, it's a lot more versatile.
However, I have always found that trying to heal adjacent areas was a nightmare, because the first brush kept being activated when drawing a second.
What I have recently discovered on another forum is that the behaviour changed with Lightroom CC / 6.
When you select the tool, you get a "Tool Overlay" option at the bottom. I had thought that just showed where the various brush strokes are, but no. If you select "Never", you can now brush anywhere without interference between brush strokes.
Maybe everyone know this, but I didn't!
Dave