I’m not really sure how well it shows accuracy though because there isn’t really any context to any of it. Great for showing if something is identical but beyond that it’s sort of just largely meaningless numbers and noise.
It’s likely that something that has a deep null with a source probably sounds very close to it, but when comparing a few different profiles, they could all null to a similar amount, but in areas we perceive differently (either based on the source, the frequency range, the amplifier, the tone, the playback system, the users ears). So you might get a range of different numbers but I don’t think they really correspond to anything meaningful, unfortunately. Guitar tones are too complex to measure like that IMO.
I think listening is far more informative, even if you take in the massive variable of playback systems and people’s hearing.