Complex sentence: His two principal technical objections were termed the "fat fingers problem" and the "sticky fingers problem" that he believed would exclude the possibility of "molecular assemblers" that worked by precision picking and placing of individual atoms.
Split into simpler sentences: His two principal technical objections were termed the "fat fingers problem" and the "sticky fingers problem". He believed these would exclude the possibility of "molecular assemblers" that worked by precision picking and placing of individual atoms.