Well, we all have opinions and that's what makes things interesting. I will state my understanding.There were multiple styles in making Proof coins around the world. In US, for example, there were a few different Proof coin styles - mirror (brilliant), satin, matte, sand blasting. But, what separates Proof coin from regular business strike is not "brushed special finish", but the entire process. There were carefully prepared dies polished to a mirror like finish, planchets were also specially prepared. Each coin was struck slowly and carefully, sometimes more than once to have full details of the design. As a result, these Proof coins have multiple Proof characteristics, not just the mirror like fields and edge and frosty reliefs of the design. One has to also look for squared-off rims and such. And just because the Proof coin displays the signs of wear or cleaning, it does not make it non Proof. For example, you can see NGC grading coins as PF-58 or lower.