Rivkin,
When you go to lesser quality blades, kanteisho are just papers and you don’t pay thousands for them. The old papered or non papered blades in dealers shops are the ones which are not judged worth a shinsa price. Now for the others (corner shops) bundled swords, naginata, yari are not sold as papered swords but rather as souvenirs
Arnold,
I entirely agree with you, there are real experts/scholars in both NTHK organizations and I am sure that their kanteisho are as valid as NBTHK ones, even if in the Nihonto world they are not considered as good as NBTHK ones for historical reasons rather than objective reasons. I am sure that some green papers are valid but should I be in the States, I shall double it by an NTHK kanteisho as the North American market is used to them. You described exactly my mood about sending a blade to Japan for papering, too much hassle/too expensive. I don’t need to have my blades upgraded from Hozon to TH as their quality speak for them. That is the reason why I buy my blades in Japan and have them papered before sending them to France. In Europe, NBTHK prevails...