Although beeing European and not familiar with the mentioned rules, please allow me to try to comment anyway.
All tests/rules for valves, all over the world, have mainly four general purposes:
1. To ensure that measurements, materials and general metal (material) construction of pressure bearing parts (main construction) are OK.
2. To ensure that the finished valve body/pressure bearing parts (with open valve) can withstand a given pressure (given test pressure by given standards).
3. To ensure that the finished valve can operate properly and seal as described over the seat sealing according to given specifications.
None of theese three points exclude the other, and you will often find that the one overlaps to some extent the other.
4. In addition you will have a fourth set of diversified additional rules and tests, as for instance: singel special material tests, painting tests, corrosion tests, emission tests, extended function and operating tests, fire tests, etc. etc.
The end user, or the market (and the valve producers you compete against) will largely give what minimum tests and rules you have to include in your normal production standard to have a high-quality competing product.
If you deviate from the test description given by an authority, you will not have a proper test recognized or qualified by QA-control. If there is doubt on how to understand the test text the issuing company is the only one authorized to answer you.
In some (seldom) cases the description is 'old' in the context that production or construction (by new materials or methodes not available when the original text was described) ought to lead to a correction of the text, but this is not (yet) done. This does not change anything on your side.
Summary: you need to follow the described procedures, even if it gives 'no sense', but nothing will hinder you to put in additional tests to prove to the market that you have a high-quality product.
PS. In some cases a non-painted metal construction that is pressure tested can reveal leakages and materiel faults not occuring when painted.
Anyway, a completed and finished (painted) valve, not pressure and function tested, both for house and seat leakage will be a step lower in quality and preference scale than one from a factory testing all valves for this.
If still in doubt ask your customer directly what tests to use or suggest what you find best.
Good luck!
