While he is slow witted bigger doses do give bigger gains generally, as much as that sucks. However, it is not a linear relation and while 500mg can give you 25lbs, 1.5g may give you 30lbs. Not worth the extra risk and money.
I have to agree with BoCephus2 230# at the height of 5'9 and with 6% BF he must look huge, i know if he was 5'11 or 6" it wil be completely different story.
Well my first cycle I maxed out at 400mg IP Deca/week and 25mg pinks/day and put on 30 pounds in 8 weeks.... You definitly sdont need huge dosages to get great gains on a first cycle.
I usually tell people to go high...period, but I would never tell a newbie (2nd cycle) to start that high. My advice is to feel your way through it. Alot depends on diet training....etc. Judging by your comments about his drinking, drugging etc....he's probably not doing the right things anyway.
I'm 5'9" and at my best have competed at 247lbs...on half that dose.