What do you find contradictory? I have seen irresponsible breeders post no need to test as "they don't have it in their lines" or "test not worth anything"… but most responsible breeders and owners tell you to do the linkage test (especially if breeding, but should be by everyone), strip monthly and follow the Protocol if your dog develops fanconi.
Read all the quotes and statements on Fanconi and work out how contradictory it is for yourself. I don't think many UK Basenji owners do a Fanconi 'strip monthly' and certainly some breeders do advocate no test. Are such breeders irresponsible not necessarily. A 'probable' diagnosis on any medical condition is hardly a scientic diagnosis to say the least but testing is better than not and is certainly better than doing nothing.