I not think that, but they did show that "Not more than three passes" doesn't imply kick-and-rush. My comment was triggered by your statement "time moves on".
So, the math still may be right.
For an extreme example, scoring without possession is as good as impossible. That could lead to a rule "keep the ball"
However, that doesn't imply one should optimize for possession alone, as the way to maximize possession is to play backwards when even pressed a tiny bit, scoring own goals if needed to keep possession.
Also, I don't see huge defensive benefits of possession if you want to win. In the end, it is about two teams both getting equal number of possessions (+/- 1), so to score (which is needed to win), teams will want to maximize their chance of scoring on possession and to minimize that of their opponent.
Only if your chance of scoring is lower than that of your opponent or if you are ahead 'enough' (where 'enough' depends on time to play and speed of you opponent), you will want to minimize the number of opportunities both teams get, even if it means your probability of scoring on possession goes down.
The main issue I have with Reep's analysis is he seems to ignore the defensive benefits of possession.