Speaking to MPs on the Commons science committee yesterday (9 December), the Government's Chief Scientific Adviser instead called the curfew a 'policy decision', designed to limit the amount of time people spent together indoors - where there is a greater risk of Coronavirus transmission.
The imposition of the curfew back in late September led to a mixture of anger, confusion and dismay from operators incensed by the baseless restriction, which led to people filling the streets en masse at 10pm each evening after visiting restaurants and pubs.
Vallance said: "There's no real hard evidence on curfew times.
"What you can see across Europe and indeed in this country is that keeping people together longer in an indoor environment, where there's also alcohol, is likely to increase risk.
"And therefore that was a policy decision around trying to reduce the potential of interactions.
"It's not something you can model with any degree of accuracy and say a particular time will give you a particular result."
Last month, in what could be best described as a pyrrhic victory for the sector, Prime Minister Boris Johnson announced that the 10pm curfew would be extended by an hour, meaning hospitality venues subject to (the now tightened) Tier 1 and Tier 2 restrictions are now able to take orders up until 10pm and then be closed by 11pm.