Well, I am shocked as to what I have just read, " I feel my son has been treated harshly considering the small excess".
Firstly, He should have not really had ANY drink, knowing he was going to be driving, however, he did so, more than 1 pint obviously, and the number of pints he consumed, put him over the legal limit, which he ran the risk of as soon as he picked up the pint. There is ALWAYS the chance of a accident on the roads, as most drivers, and those with common sense know, he got caught, maybe he was unlucky, regardless, he was OVER THE LEGAL LIMIT, it may have been 6mg or 60, still ILLEGAL. Maybe after his driving ban is over, his insurance has rightly so INCREASED, he might regret his actions. How would you feel if another motorist had collided with your Son, example, if he was innocently crossing the road, and this motorist, who was 6MG over the LEGAL limit, had seriously, if not fatally injured your Son? Would you say that any sentence handed down by the Courts was "harsh". I highly doubt so, so don't expect pity, as I for one, will NOT give it to you.
Oh yeah, before I finish, How much remorse is your Son showing? Bet he is more sorry he lost his licence rather than regretting his actions!