You know what's odd, though? Both parodies were written by Desmond Devlin, who is IMHO about the only MAD writer these days who's actually funny, especially when satirizing comics. On the old s_d I posted some brilliant parodies he did of Sandman: Endless Nights and Cathy as if written by Frank Miller.
Maybe Devlin wrote the movie parody on an off day, or was strictly instructed not to deviate from the formula of "just say over and over how bad and stupid the movie is", which is what basically every MAD movie parody has consisted of for the last 20 years.