The fat on a women's chest is shaped that way because of the hormones releast. The fat on a mans chest starts on the chest, hangs down and then rolls under the arms. Essentially for a person of that size, their arms would be pushed further outwords due to the fat under their arms. Also, if someone was that large, their exessive breathing would mean a larger diaphram, pushing the muscle under his chest further outwords. I think the legs being also more defined would help, as a guy that big would need some real fire power in his legs just to get through the day.
It's coming along nicely, I hope my crit helped.