Last year I was walking to a spot in the same park. I was mindlessly swinging the coil as I went and suddenly had a beautiful tone that stopped me in my tracks. I turned back around and couldn’t find the tone. After backing up a step or two and repositioning I found the tone again but could only get it at very limited window of attack. I believe I could get that signal in both directions but a slight position change would make it completely vanish. It was a Barber quarter that was only about 4 inches down. That was proof positive for me of the capabilities of the 6 inch coil in heavy trash.
I think most signals with the 800 that end up being good targets will repeat left and right in a given position but are not necessarily always obvious dig signals. I’ve dug coins that were bouncy, faint & weak and/or uneven from left to right.