@lewm I'll try to answer all your questions -
When I found static on he LP, I could hear it crackle and pop as I picked the LP up. During playing I could hear a constant snap and crackle quietly in the background. This is unlike a click or a pop from a damaged record or perhaps a dirty one.
Gruv Glide has you do a test - play a track several times to become familiar with it, then treat it, and play it again. Untreated I had static, post treatment I had no static and it sounded noticeably better.
The static removing camel hair tonearm brush isn't conductive, in spite of the claims by the manufacturer. All the static removing manual brushes I have are conductive in the range of kOhms. The tonearm brush is more than 20 Gig Ohms. If this reduces static, then I don't see how. The manufacturer told me to wash it in soap and water, then rinse, and dry it. I did, but it is still non conductive. I also rinsed it in a solution of fabric softener, thinking that might help conductivity. It did not but then I only added a drop to an ounce of water. Frankly, I question the claims the manufacturer makes about static. At $300+ it "should" do a great job at static! It does, however, do a great job picking up any dust, so I continue to use it.
I don't have an static meter or any way of measuring static. I can tell you that sometimes the static was so bad, the hair on my arm prickled up before I got to the record.
I'm not making any claims on how the static got there- - I've read all the previous posts.I only claim static was present before and not after the Gruv Glide treatment, plus the sound quality was better.