When I measured Manfred's arm at the Arnold, through a thorough mix-up, the photographer who was to record the event, did not show- perhaps because the schedule was bumped ahead (earlier) by 30 minutes.
At any rate, I was later told that some German television station recorded the measuring, but I have never been able to confirm it.
The only photos I have of the event are grainy shots taken from too far away by a friend.
Here's a gimmick you can use. If someone is working for a supplement company at a booth, ask if you can snap a photo of the can of protein powder right next to his bicep. Have a friend hold the can so that the bottom of the can is on the same plane as the bottom of the arm.
This will not be exact, by but knowing the height of the can, you can determine if the height of the arm is taller, or not. Manfred's arm was 10" tall when I measured it with calipers- and it was taller than two Pepsi cans we placed next to it.
Priest told me that he could add an inch by pumping his arms, which is reasonable. With lower bodyfat at contest time, arm size would decrease, and perhaps this is why so many bodybuilders are allergic to the tape measure near an event?
When I asked to measure Dillet's arm in Atlanta at the Olympia, he said I could measure it at the Arnold later...
As with lifting claims, measurement claims beg for verification, but usually no satisfaction is forthcoming.
Does it matter if someone's arm is 22" or 24"? Only if such a claim is made by the person. Then it is time for proof.