Churchill was overweight and he wasn't too bad of a dresser. If you want to see more realistic examples than on the sartoralist then checkout the styleforums thread "what are you wearing today", mentioned elsewhere. Suits work best on someone who is around 5'9". I am quite tall, which means I can look a bit goofy if I wear the wrong things, but just like with being overweight, it is possible to put together a combination that looks good.