Well, my law school is in Germany and I am a law school lecturer, too. So maybe I am a bit older than your name Travelkid propoes. With all respect, I believe it is you who has either never taken the lessons or missed them. Unfortunately your legal evaluation is too general and appears to be copied from a consumer magazine. You make the same mistakes my first year students tend to make: Simple put the burden of proof on somebody without analyzing the language of the contract.

Your are right: "What is relevant is the principle of burden of proof." We agree on that. However, you fail to define what has to be proven.

So lets go through this step by step. The customer signs a contract that entitles him to transportation:

- of the the pax nn presentation of the ticket
- of up to 20 kg of checked baggage
- of up to 8 kg of hand luggage.

Agreed?

If so, it is the pax who claims, who demands something. And as a very general principle of law the claimant is required to proof his entitlement. So if you are at the gate and the agent refuses to accept your luggage you need to proof that your luggage was within the contractual limits and that the agent/airline breached contract. You demand something, you need to proof.

You approach would only be correct if the language of the contact were "you are entitled to one piece of handluggage unless it is heavier than 8 kilogramms". However, this is not the language of the contract (even if you want to read it like this). The language is "you are entitled to one piece of handluggage for up to eight kilogramms".