This is dead on.
My father was on the investigative (permission) side of ATF. His techniques were similar. He particularly liked to get responses in bits and pieces over time, so that the slips would show up. He was always smiling and interested in the lies someone was telling and would encourage them to elaborate on them. then, later, he would refer to it again and watch their responses.
I know a retired journalist whose interview technique is quite similar.
I resemble that remark.
And you are right.. going over the same ground separated by time .. can often establish that the subject can't remember which lie they told the last time.