Adam, first the B&M and now the clay. What the heck is going on???
It most certainly is not a placebo affect. Zaino (along with most sealants) will cover a lot of the contaminants and make a surface smooth. But as the sealants wear down, the contaminants will still be there. A clayed surface vs. a non-clayed surface should feel very different. There is no way that your car doesn't have contaminants embedded in the paint if you've driven your car at all. Zaino is giving you a false impression that the surface underneath is clean/smooth. I compare it to washing your car with soap and washing with just a water rinse. Both cars will look clean, but only one will be truly clean.
Again, I'm baffled by your expriences. But whatever works for you, go with it.
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