I call full BS on your post LeadSled, as above, it is simply incorrect.
How many experimental aircraft have you built, maintained and modified and had C of A’s issued for?
The builder is the manufacturer and is entitled to make modifications that are not major, without the need for a new C of A.
I personally rebuilt a written-off aircraft, fitted a different engine and propellor type, re-wired it and fitted all new avionics and after consultation with casa, it was not considered to be major modifications.
You are also wrong in that the AP doesn’t inspect the aircraft. They simply review the paperwork is in order and sign the appropriate forms. RAaus do it a little different in that their delegate watches the builder perform their final inspection and double-ticks the checklist.