Placebo does appear to provide quite a bit of magic for Rett patients and perhaps not least their subjective score givers.
Just like studies show that more expensive placebo versions of a treatment provides more effect than a cheaper one. Expectations for A2-73 have commensurately probably also been much higher than those for trofinetide, as reflected in their respective trial results.
What we are looking at is to likely a large extend a notoriously difficulty in measuring with any accuracy treatment effects in Rett as an indication without established objective biomarkers.