I took my PPL ride with a 250+ lb examiner. I was about 190 at the time. The plane was a Piper Tomahawk, and the tanks were 1/2 full. When I did the W&B, I found we were 18 lbs (3 gallons of avgas) over max gross weight. The examiner asked what I planned to do. Being a well-trained Army aviator, adept at following the rules, I told him I was calling the fuel truck over to have them pump 3 gallons out of the tanks. He told me if I did that, he would flunk me for "poor judgement"... He told me to just do my taxiing at high throttle settings, and we'd burn off those 3 gallons before takeoff. (Nope - that "taxi fuel" was already factored into my calculations...) I just nodded my head, and resolved to be extra gentle with my maneuvers until 15 minutes into the flight... But I gotta tell you I was pretty uncomfortable with that whole experience! I kept looking around for the "Candid Camera" crew...
After we landed, we had a serious discussion about W&B considerations, with him thinking he was educating me on the "realities" of the world... (I didn't tell him that I was an Army helicopter instructor pilot with over 1000 hours instructor time – just let him go through his spiel...) He basically said that airplanes seldom weigh exactly what the logbook W&B form indicates (true in my experience). He claimed that airplane weights vary by as much as 30 pounds, and are usually less than "book" weight (not true in my experience – every airplane I've ever had weighed came in at least 30 lbs heavier than the "current" W&B form stated). His claim was that if you were within 30 lbs (~5 gallons) of max gross, that was "good enough" to be legal for flight. Later, when I shared what he had told me with my CFI, he turned purple with anger. He knew the examiner, and called him on the phone to have it out with him. Apparently, the examiner admitted he was wrong, and that he should have let me have the fuel drained as a "learning experience." But he still felt like it was OK to fly when you were 30 lbs above gross weight – anything within 10% of gross weight (which would have been more like 160 lbs!)... I learned later that either the FAA revoked his examiner's certificate, or he voluntarily surrendered it. Either way, he was "no longer available" for pilot examinations.
Years later, when I got back into flying, I flew with an outfit that flew LSA Sport Cruisers. Great little planes – fast, comfortable, and very efficient. But to stay within legal W&B limits, I had to find a pretty slim instructor, and even then we could only fly with about 1/2 fuel – which was still enough for about 2 hours of training, landing with a 1 hour reserve. Like I said, great little planes!