Yesterday evening departing Edinburgh, No1 son tells me that the pax were informed by the flightdeck that the (30min) delay was due to 'de-icing and helping an assistance passenger'.
Oddly, he (and presumably most pax) didn't think anything of it, until I told him he had been lied to, as the OAT was +9C.
'Delay due to operational reasons' would have saved the crews' credibility and the assistance passengers blushes.