It can't be any worse than the London Underground in winter.
However, it occurs to me that this might be a splendid way of getting an on-board upgrade.
Arrive on board, strap in to you 17 x 28 inch economy class box and immediately put on a surgical mask.
When questioned about the mask by the cabin crew (who are immune to all this?) say in a loud voice that you understand the company is screwing around with the "air conditioning" in order to save money and that you are taking no chances.
Bet you get an upgrade
