OK, Lorenzo, I bow to your strict aherence to protocols of the experts. "In the style of" is fine with me. However, common sense, which I heartily believe in, tells me that the preponderance of evidence points towards the possibility of authenticity. Just my opinion, think of it what you will...but...
...a "treasure/gem" is in the eye of the beholder, and having been educated and trained in the visual arts and crafts, I believe my eye is pretty damn good. My enjoyment of this tsuba is strictly a personal, and while I would hope others might likewise enjoy it, I make no pretentions of deciding how others should think about this piece. Sorry if the syntax gave a different impression.
"You can't have one of the greatest higo master work this cheap and if you do than the seller is probably insane."
Are you refering to the price it was sold for? If so, I'm sorry you feel that Skip Holbrook and Grey Doffin are probably insane.
Colin