Which garbage collectors are you talking about, exactly? I presume you have particular Common Lisp implementations in mind, given your second comment. As the au

Which garbage collectors are you talking about, exactly? I presume you have particular Common Lisp implementations in mind, given your second comment. As the author discusses, there are more lisps than Common Lisp, and certainly more varieties of fundamental data structures than cons cells (regardless of the specializations certain implementations have towards optimizing them). The provided link to the Steele talk on optimizing parallel computations over diverse collections is quite relevant. (Meta: is creating a sock puppet account really necessary to rag on a blog post?)