Kavanagh wasn't referring to the tart as clay, at all. The clay references only the mysterious dichotomy in human existence, the "art and soul" of living, symbiotically related to, but simultaneously to be sheltered safely from, all issues material to the corporeal dwelling. There is no tint of judgment or condescension whatsoever. Cluin ingeniously referred us to Donne, and Donne provides the clue: "Now all the parts built up, and knit by a lovely soul, now but a statue of clay, and now these limbs melted off, as if that clay were but snow;" In other words, Kavanagh had merely failed to protect his soul and his art, nothing more grave than that, but with devastating consequences.