“Sheer Heart Attack” was half-finished at the time of the eponymous album. Roger Taylor sang lead on the demo but for the definitive version the band decided Mercury should co-sing lead vocals (probably based on the fact that May had already sung two songs and Taylor one). Guitars and bass were played by Taylor, apart from some guitar “screams” by May during the instrumental section.
During this time, the punk rock movement went into full effect, and this song was viewed as something of a jab at the musicians who felt bands like Queen were too self-indulgent. Of note is the lyric “I feel so inarticulate”, and the fact that Taylor stated in interviews that he thought many of the 1970s punk bands had very little talent.

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