no. there is no limit to what anyone can do. i just favor the crane techniques cause theyre very practical. the fact of it is that, if you practice the five animals system (crane, snake, panther, tiger, dragon) you should learn them all and use them all harmoniously at the same time (i mean when the technique is needed). theres a five animal kung fu style i beleive but also there are styles like choy lay fut that teach a five animals form that uses the same concepts. but then again there are styles that focus on singular animals. (white crane kung fu, emei snake fist kung fu, eagle claw kung fu, monkey kung fu, black tiger kung fu, seven star mantis) also theres styles that combine two animals (wing chun [snake and crane], hung gar [tiger and crane])