From my experiences, I can distinguish pheromones (or their absence) and any artificial add-ons (like perfume). For example, in my personal preferences' beauty scale, all asian girls are capped to 5/10, no matter how beautiful they are. I studied with many of them and was friends with few and smell-wise, all were incompatible. There is no "negative" body smell, it is just very subtle; weak and strange. Like, imagine vegetables you never ate but they smell strange so you don't want to try them. From other side of spectrum, in my preference scale, black girls, specifically from Caribbean area (Cuba, Brasil, not Africa) are also capped, to 5-6/10. However, all "specimens" I encountered have strange "pull" in the smell and it makes me forget about the cap and flirt and hang with them. I once nearly fell in love with a girl from Brasil who was 6-ish but radiated pheromones like geyser. Smell-wise it was probably a mix of body oil, perspiration and pheromones. Practically, for me, enticing pheromones are as strong as perfumes, but by magnitude more richer. "Negative" body smell/pheromones is weak, strange, yet not off-putting, just strange. That's how smell (in)compatibility manifests to me.