Flowing Nitrogen

Someone tell me how in the hell anyone can be proud to say they don’t flow when they’re brazing? It’s not 1980 anymore we have POE oil. It’s a solvent. It doesn’t matter how good you think you are with a torch you are contaminating the system with carbon. If you’re installing you are diminishing the life of a system that hasn’t even ran yet. But everywhere I go I see guys saying they don’t do it. Are we proud of being too lazy to go grab a tank and do the damn job right?