Agrajag,
If your aircraft is a home built aircraft (Experimental Amateur Built) you do not have a C.of A. Even if it is the very old style AABA certificate, the document is still not a type certified C.of A.
Your "POH style" document is not "approved" by anybody except you, it is just part of the document package you submitted to get whatever certificate, on which you fly.
"Certificate of Airworthiness" and "approved" have very specific legal meanings in certification terms, they are not generic terms.
Yep, agreed. I was perhaps a bit casual in tossing around such definitive terms in the context of an Experimental. But my point (perhaps not well made) was that there is much omitted or only vaguely covered, and therefore left to good judgement, even in POHs for certificated aircraft. On that, I suspect we also agree.