As it’s been recently stated, DP does not have the ultimate taste in recreation clothing choices. Apparently, neither does she posses any innate ability to do step aerobics.
PH was so distracted by the young woman’s arm flails (and they were positively flailing!) that she almost misstepped a few times. Literally, she could not imagine someone who was further from following choreography in her life. Smugly, shallowly, PH thinks, “I am five years older than you maybe more and I am doing an insanely better job keeping up.” PH is weirdly competitive – this is not a good trait.