Johnny Herbert says that the Formula One calendar could expand further but admits to having some reservations about whether it should do.
In 2020, the Formula One calendar continues to bloat. With a record 22-races through the additions of Vietnam and The Netherlands, questions are being asked about whether the calendar is already too big to handle.
"One thing that's different from when I did it, and we did 16-17 races, was that we probably did 30 days of testing," said Herbert. "If you did it as a bundle of days away then we probably did more than what they're doing at the moment.
"Back in the early '90s there was a Friday engine, you change it, a qualifying engine, then you change that and put a race engine in. Then there was a warm-up engine on Sunday sometimes, so there was possibly another engine change before the race.
"They [the mechanics] did 24 hours quite often.
"The difference is that we had Australia, Japan, North America, Central America. Now you have the diversity of Abu Dhabi, China and Vietnam coming our way, so a lot more flying.
"I always find the second part of the season is a killer. There are so many time changes and flicking backwards and forwards. That takes a toll."
Pushed for a number, Herbert added, "As a whole, we're probably not too bad at 20-21. Going up, is it possible? Yes. Doing the triple header [in 2018] was a big mistake showing that was possible because it means we can do it."