To be fair I only used his quote as it listed most of the points well but this is quite a widely discussed and observed “phenomenon” these points are also applicable to reducing stress and reducing hermies and we all know plants can become hermies through stress.
We should give him a little bit of credit as I’m sure he’s seen his fair share of plants being grown, but I do agree it’s very time consuming difficult to try and prove these points but they have been observed by multiple growers for many years so don’t discount them completely.