Socal, thanks for replying, but:
1. in my first paragraph I did put 'rating' in between '... ' and in the second one did talk about training/approval. You are correct that endorsement would have been a better term. But then again, the key-topic was about the legal aspect.
2. For the example listed to illustrate the main topic I intentionally refer to rating and not tailwheel endorsement.
In any case the posts of B2N2 did put it very clearly - thanks for the confirmation (and disclaimer) .