The opinion
MILLER, Judge
(concurring).
I fully agree with the majority opinion, but I believe it should be pointed out that the issue of diligence during the entire “critical” period could have been settled —all at once and a long time ago. The board in the original case declined to discuss, much less decide, any matters relating to diligence during any period other than October 4, 1961, to January 12, 1962. Thus, our review in the original case was limited to that period, and our decision of July 1, 1971, triggered further proceedings in the Patent Office leading to this appeal to close the gap left by the board’s first decision. Loss of valuable time and expense to the parties, the Patent Office, and the court has been the result, and the patent to Watkins has been delayed for over three years. The practice of avoiding piecemeal decisions whenever possible is to be strongly encouraged.