Werleibr, like you, I started out with 25=y when choosing my document (the 25th word was quick and easy to count to, so it was my pick). Little did I know that was the only letter of the group that didn't match the criteria. I decided I was missing something and quit trying to solve it for the night (Jan 31). Then, the day before yesterday, I didn't get a chance to pop in and check the thread, so when I looked last night there was a lot of new information, hints, and your excel program results. I was about to pull up the D.O.I. again and decode. I didn't even have to go try again to decode the message, you had already done it, other than the "a", which I just decided was an error on either the encoder or the decoders end. You put a lot of work into it and solved it without realizing it. I just happened along after you did all the work, so I would like to give the sapphire to you.
Thanks Cappy, it was interesting! Please send it to Werleibr if you all are agreeable to it! He really solved it more than I did, my part was just solving the little twist at the end.