John Field joins the discussion

1. John Field
I don't know how they did it except that it was a code. It had to be because Sydney did it with Russell Braddon and his second wife, so it was not a special gift as Braddon suggests in his book on the Piddingtons. I reckon that a reading of the scripts (which are in the Australian National Library can can be bought) will reveal the code.

A very good friend of mine (also a magician) had lunch with Lesley about 5 or more years ago. She refused to disclose the code but made it clear that she did not enjoy the "success" years and was glad when it was all over.

2. Martin
My research reveals that she argued much with Sydney over his frustrations. These were mainly due to letters he received from the public. In those days the BBC passed all 'listener letters' directly to the Piddingtons, so they would open them over breakfast. Many were nice but others were mean and critical. Sydney reacted to these letters and hated anyone ever offering a theory about his methods. Even if the critic was way-off, Sydney knew that others may believe it to be true, and that drove him to add more controls to his demonstrations to help dispel such ideas. This always caused Lesley to want to shake him into being thicker skinned. She hated any changes because it often meant there was room for more mistakes, which annoyed her. This pet-hate created the first cracks in their relationship it seems.

Tony Griffith 3.
The fact that Sydney did the act with Lesley, Russell and his second wife shows that the act could be learnt, and as John says, it wasn't a gift.  I think I explained in our earlier correspondence that I think they used a variety of methods depending which 'trick' they were presenting. It would be interesting to know the extent of their repertoire.

So the story develops. Sydney reads an article about Dr Rhine's experiments while in Changi. He and Russell develop the act using their knowledge and experience.   

So something that was developed to pass away the time in Changi then develops into something much bigger with the BBC series and the subsequent theatre tour culminating in The Palladium finale.

Sydney's closing lines "You are the judge" would naturally prompt listeners to engage in speculation. What was in Sydney's mind at this point? Had his ultra ego taken over and he thought he was infallible? Perhaps some of the listeners writing-in actually hit the nail on the head as to the method and pressed some of Sydney's buttons. No doubt Lesley was correct in that he should have been more thick skinned and not taken it to heart..... leaving it simply to his closing line...."You are the judge."

Over the years I have seen this sort of thing happen to one or two magicians I knew, when they took matters far too seriously, sadly ending in the breakdown of relationships. Lots of wives act as assistants in their husband's act, sometimes a little reluctantly.
It would have been interesting to have been a fly on the wall when the two of them first met.   Was Lesley a real willing participant in the act or had she to be persuaded to do so?  Your comment about her not enjoying her years of success might indicate this. Whichever it was, professionally, they were a great success while over here, despite whatever the situation was in their private lives.