Ha, I do appreciate the humour though (no sarcasm on my part).
The "fine grass" is showing very abrupt seesawing of the frequency response ranging in the region of 2-3dB, I can imagine this changing the sound perception of things like instruments and voices that sit across that frequency range - you'd think it could almost be like putting them through a fine-grained filter where parts are regularly omitted (a bit like the audio equivalent of looking at the world through a screen mesh). In terms of real world observations, I own a Hifiman HE4XX which also exhibits a lot of these "fine grass" deviations, I measured it on my miniDSP EARS rig and it stands out as having this characteristic in contrast to all my other headphones I've measured on it (which are dynamic driver headphones that don't have this "fine grass" deviation), and even though I can get the tonality of the HE4XX spot on when using an Oratory EQ it's when I compare it in the same listening session to some of my EQ'd dynamic driver headphones (that have smooth frequency response) then I can resolve more detail in the dynamic driver headphones - so eventhough tonality is spot on with EQ'd HE4XX it lacks something in it's resolution which I put down to it's unique "fine grass" measurements vs my other headphones.
EDIT: following is my HE4XX measured on my miniDSP EARS rig to show the "fine grass" deviations I've been talking about (even this HE4XX has less "fine grass" than the Susvara). Note that the overall shape of the frequency response will look strange as it's measured on miniDSP EARS rig and not on the same GRAS rig that Amir & others use, so ignore the strangeness of the overall shape.
View attachment 336792
EDIT #2: and a smooth dynamic driver headphone K702 measured showing no "fine grass":
View attachment 336799