Jim,
To be honest Keith - I would much rather take my own personal experience and a lifelong interest on the subject to a hastily sought out cut-n-paste from Wiki

I want through that wall without difficulty - on a train - it was no different and probably a damn sight easier that if I wanted to fly from Shannon to America

How often did you come under fire leaving Shannon for US. Well done for surviving.
Were many killed, mutilated and maimed by land mines and directional mines on the fence?
Did you see large numbers of your fellow travellers dragged off to long terms of incarceration?

I suspect than as an idealistic young communist visiting the communist world you saw what you wanted and expected to see, and ignored the unpleasant fact that the people had to be prevented from fleeing it.

"Those caught in the act were often tried for espionage as well and given proportionately harsher sentences.[130] More than 75,000 people – an average of more than seven people a day – were imprisoned for attempting to escape across the border,"