It wasn't a theory - I was giving an opinion on why a mother, on holiday on the continent on finding one child missing and the others seemingly in an unnaturally deep sleep, might jump to the conclusion that her kids had been sedated. That reason being - media stories in the press (of which there have been dozens over the years) of holidaymakers being gassed and robbed. If you re-read my post you will see that that is exactly what I wrote and there has been no change of view or "volte face". Thank you.
Not that I consider it an important point, but were there really numerous stories of gassings predating May 2007?
I believe the two links you provided are more recent, and personally, I am not aware of a history of these incidents.
I have to say I am dismissive of such gassing being used in burglaries. In the French example, there were young children and adults present. My knowledge of anaesthetics is limited, but I would have thought the dose required to sedate adults would cause damage to the young children.
Apart from a case of blistering, these occasions seem to have no after-effects. No one is woozy or sick or has a headache. No one notices a residual smell.
I seems to be magic gas, which is why I place no trust in these reports.
Now, I understand that you are saying that IF Kate had read of such reports before Madeleine disappeared THEN she might have thought of this. But were such reports common or common enough before May 2007?