Back to this topic, that AD1.1-3 section wording comes from ICAO template, that template was initial proposed by North Korea, Venezuela, Sudan…as it strictly prohibit flying operations in non AIP aerodromes
I would say, that wording out of touch with reality of private operations and things like Schengen….I think the intention was “scheduled flights”, “civil aviation”, B747 and A380
Some countries like Italy & Spain and even USA did a great job in AD1.1 to explicitly say it’s not an issue for ultralights, private aircraft and only apply to airliners
Some countries like France & UK, prohibit international & national flights to AD that are not in the AIP, if one is naive enough to believe AD1.1-3, there are no ULM or Microlights strips in France and UK as far as AIP1.1-3 is concerned 
I think Poland just copied that entry as well from ICAO template, hope the explanation takes some mystery away
Just ignore when you fly Poland-Germany
Here is what UK say,
Here is what France say,
Google Search on that wording comes handy, almost every AIP has that crap written…
