Peter, are you saying you set out at 02:00 for a 8 hr round trip? “More or less without a break”. I seem to recall that you have admitted to being age-beginning-with-an-8. At 02:00 your system - everybody’s system - is already low and heading downhill, bottoming out round about 04:00. It’s dark…
As an ex-professional at the wheel, I would say “Bad lad. Don’t do it again”. I had ten years [age 30-40 y] running a location truck [‘Nation’s Locations!’] for TV/film/photo shoot crews. Then a spell, for 5-6 years, as driver-guide on 16-seater mini-coaches for a tour company and, after I declined to renew my PSV licence at age 60 on the grounds that my night vision had declined to the point where I decided I was a danger after dark, occasional spells of industrial delivery to top up the meagre pension contributions.
The main rule for a day’s driving is the mandatory 45 minute rest [this can be 30 + 15 or 15 x 3] after not more than 4 hrs 30mins at the wheel. So if you had been driving a vehicle with a tacho, it should have shown a total of 90 minutes rest.
It is a problem, private motorists assessing their own capabilities. As I mentioned, I stepped away from a job I really enjoyed - battlefield guiding - because the company policy was that the guides were also the drivers.
I did not want to repeat a situation I had on a return trip from Arras, whereby, delayed 2 hrs by missing our Chunnel slot, the last two hours Swindon-Cheltenham were in the dark. Nobody on the bus will have been aware that I was absolutely terrified and making the usual supplications to Big G as to my future behaviour if he got me to Cheltenham with all pax still in once piece. I quit next day when I got the bus back to HQ.
I have a pal who has never, to my knowledge, ever admitted to being anything but perfect in every way - except he has admitted he has the same night vision problem. An optician confirmed that it is an age-related condition.
I have a camper van the same size as the 16-seatercoaches and my location truck, a Renault Master LWB/Hi roof. Making the trip from Valencia to Calais, as I have done many times over the past 6 years, the hrs/day I have allowed myself have come down from 7 - 8 to 6 - 6.5
It is more tiring driving my van than a passenger car. But, faced with the trip you described, I would not have done it, most certainly not setting off at 02:00
There’s that grim joke, “He died peacefully in his sleep. It was the others in the car/coming the other way who went to their deaths screaming”