In mid-December my father removed the snow from my car with a stiff broom. It left ugly and quite deep scratches on the trunklid (new Spring Project).
We washed our cars together with a pal, who is a body shop guy and has quite good skills (as I thought) with the rotary.
He said that he'll remove it. OK. Out came the 3M P-III Trizact compound and removed the defect in no time and left an LSP-ready surface. That was suspicious for me because it worked too fast and left a perfect finish. I thought: A polish can't be that good! But I was pleasantly surprised nevertheless. I threw on a coat of 845, and we were finished.
Then came yesterday. I washed my car with my usual Sonax Gloss Shampoo/garden sprayer-foamer (Which in fact produces pretty good foam!) routine. I was surprised because the water was pooling on the trunk. How can it... Washed once again. I thought that it must be the 1Z -90°C windshield wash. Maybe it is too harsh on LSPs...
But I noticed that the water pooled exactly on that particular area where my pal polished the surface. After drying, I had to realize that the broom scratches are still there (lessened) and additionally, there are disgusting buffer trails too! The damned 3M just hid them! 1.5 months of near perfect illusion! I'll never let a 3M polish touching my car again.
This little happening just taught me that a body shop guy is necessarily just as good as his materials dictate him. The 3M Trizact did a perfect-awful work. The guy thought that it was perfect, his skills were good enough and so did I. I was sceptical though, because of the time/cut/finish factor, but anyhow, I accepted the results. I was wrong.
I'm pretty sure that the unstable filler has compromised the durability of the 845. But I love polishes because of their honesty (like Menzerna, Optimum, FK), and not because of a deceiving illusion.