Agreed.
But as regards the issue of what conditions are necessary to rebut the presumption of who is keeper, this judgment by the Supreme Court cannot be ignored(it's still on the ETA Key Cases 'meaning of keeper').
https://www.londontribunals.gov.uk/sites/default/files/keycases/francis-v-wandsworth.pdfIMO, it is immaterial that this relates to a penalty charge notice and the presumption regarding who is to be considered the 'owner', because the court's reasoning refers to different Acts and regulations which remain in common use today. I have no doubt that any court would be obliged to apply this judgment in cases of PoFA-related claims.
Rebutting the presumption isn't just that A had it in their possession on the day but B was the registered keeper.
Until I was referred to this judgment some years ago my thoughts were aligned with The Rookie's, but not now.
If others have subsequent case law which sets a different precedent then fine, I'd adopt those standards in future analysis.