This is a pretty good film, worth viewing if you have time. Many of the conclusions are what most of us would expect. Lying is social, there is a fudge factor, most people do it a little bit, while some refrain entirely and others lie with abandon.
There have been other studies showing that not lying feels very good and people like it if they can get into a situation where it is possible.
The take-away from the film for me is that people lie much less, if at all, if they are reminded to be honest.
In part, FIML practice constantly reminds partners of the importance of being honest. It also forms a social bond between partners that highly values honesty. These two features of FIML plus our simple desire to be honest with each other has allowed my partner and me to have a very good space together where we are confident with great certainty that neither one of us is lying and neither one of us has any reason to do so.