Don't put your full trust in this, but I think what it means is that the FINISHED item is solely based on your HQ parts. The parts themselves will still be affected by the quality status, and thus we can still turn NQ goods into HQ goods via the parts. The translation says HQ FINAL item, as seen below:
So I think that parts will still require those abilities and quality. Perhaps that's what he means by added difficulty; changing the way parts work.