Original sentence: Perhaps the most famous unreleased rock and roll album of all time, The Beach Boys' Smile (sometimes spelled with the capitalization SMiLE, derived from the lettering on the original cover) was intended to follow up (and surpass) their influential 1966 album Pet Sounds, but was never completed in its original form
Edited sentence: Perhaps the most famous unreleased rock and roll album of all time, The Beach Boys' Smile (sometimes spelled with the idiosyncratic capitalization SMiLE, derived from the lettering on the original cover) was intended to follow up (and surpass) their influential 1966 album Pet Sounds, but was never completed in its original form