Well that is about 5 units of alcohol every hour. It takes about an hour for the liver to process 1 unit of alcohol so at any rate you had no more then 5 - 6 units of alcohol in your body of the space of 4 hours. I don't know what others found so surprising about that. It would be like drinking a quarter of a vodka in under a hour, and even I can do that.
I'm not following.
First you said "that is about 5 units of alcohol every hour" --> where did you get this from? what is a "unit" of alcohol?
Then you said "It takes about an hour for the liver to process 1 unit of alcohol" --> so my liver processed 4 units? does that mean only 1 remained?
Then "so at any rate you had no more then 5 - 6 units of alcohol in your body of the space of 4 hours" --> how does this add up to the above two statements ?

"I don't know what others found so surprising about that." --> well everybody was dancing and shouting and singing but I wasn't !
In any case, your blood alcohol level through the space of 4 hours was about 75mg, so you drove drunk, twice over the legal limit. 100mg of blood alcohol and it is an automatic 3 year ban, fine and a depending on the circumstances possibly a 3 three month custodial sentence.
Firstly, like I said it was a mistake and I am not gonna do it again. I'm never taking the car on a night out from now on. Except maybe when I'm going to watch a movie alone.
Secondly, I was not intoxicated, my mental and comprehensive abilities were unaffected. I was sober.