cut mine all the time never harms the outcome as long as you dont go overboard . the lower ones usually die to lack of light . thoose same leaves can rot and mold . also the airflow under the plants can be beneficial . im not saying lolipop them , but reserving some of the growth energy for the top of the plant intead of repairing or shedding dead weight will not hurt .. in most instances my plants start showing better growth within a week after minor pruning then they do when left unattended .