(cdr (cdr (car ls))) vs (cddar ls)

In pcl-cvs.el:1604 ((eq (car (car parse-spec)) 'COLLECT) (setq *result* (cons (eval (car (cdr (car parse-spec)))) *result*))) ((eq (car (car parse-spec)) 'PROG) (eval (car (cdr (car parse-spec))))) ((eq (car (car parse-spec)) 'REGEXP) (cond ;; Is it a match? (The regexp must be anchored at the end of a line). ((and (looking-at (car (cdr (car parse-spec)))) (progn (goto-char (match-end 0)) (eolp))) [...] Is there any reason I should *not* change things like this to read: ((eq (caar parse-spec) 'COLLECT) (setq *result* (cons (eval (cadar parse-spec)) *result*))) ((eq (caar parse-spec) 'PROG) (eval (cadar parse-spec))) ((eq (caar parse-spec) 'REGEXP) (cond ;; Is it a match? (The regexp must be anchored at the end of a line). ((and (looking-at (cadar parse-spec)) (progn (goto-char (match-end 0)) (eolp))) [...] The one reason I can think of is that the cXr functions are defined by "cl.el", and pcl-cvs is supposed to be compatible with GNU Emacs also... But they have "cl.el" too, so why not? Another question that comes to mind is "Why aren't the cXr accessors subrs?" It seems like that would be way faster, and there may be code that would benefit from it. Is there any advantage in converting (function (lambda () ...)) to #'(lambda () ...) other than for readability? Or `((, var) ...) to #`(,var ...)?