Well, it was on the train from Exeter St Davids to Paddington, I was a business development manager for a mystery shopping company, and was due to attend a meeting with the client to review the data from their most recent results.
Wearing a new suit, jacket a bit shorter than usual, so wore a thong to avoid vpl.
Travelling first class, complimentary coffee, water etc. Went to the loo, trousers down, had a pee, then realised that although the trousers were round my ankles, the underwear was still in situ.
So, as I didn't feel I could perform the necessary contortions to place the (albeit miniscule) gusset under the hand drier, decided the only option was to bin the underwear and go commando!