“Some, like the Cossack hat, are acutely low-risk, meaning this signature gesture is probably prompted more by emotion than logic.” 

The expert explained: “The hat-touching allows Camilla to drop her head, meaning her natural tendency to look nervous and wary at the same time as lowering her own status a little is given an excuse that looks natural and believable. 

“It signals to the public that she is worried about her hat, rather than suffering from some social anxiety. 

“It’s the kind of gesture that would make people smile with empathy rather than looking judgmental or unfriendly.